43 articles trouvés pour ce sujet.
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un jardinier plantent 10 arbres |
2007-09-30 |
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yannick pose la question : un jardinier plantent 10 arbres.il a reussi a les disposer en formant 5 ligne de 4 arbres. retrouver une disposition possible Claude Tardif lui répond. |
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The height of a tree |
2020-09-27 |
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Kerissa pose la question : A man height 1.2 m standing on top of a building 34.6m high views a tree some distance away he observes that the angle of depression of the base of the tree is 35 and the angle of depression of the top of the tree is 29, assuming that the tree stands of level ground. Determine the height of the tree. Penny Nom lui répond. |
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Drawing a counter from 2 bags |
2020-05-21 |
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Sephy pose la question : Question 4: Two bags, 1 and 2, each contain equal size counters.
Bag 1 contains a pink counter, yellow counter and white counter.
Bag 2 contains counters labelled 1, 4, 5 and 7.
A counter is drawn at random from bag 1
and a counter is drawn at random from bag 2.
If the counter from bag 1 is pink, the number on the
counter from bag 2 is increased by 1
If the counter from bag 1 is yellow, the number on the
counter from bag 2 is decreased by 5
If the counter from bag 1 is white, the number is halved.
Find the probability of scoring a number below 3 Penny Nom lui répond. |
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Volume of a tree |
2019-12-19 |
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Maria pose la question : I have trees for sale. I need to calculate the volume of a tree from base which is wider than the stem.The base will be used for the making of hurleys, similar to hockey sticks so the wider base is crucial. Penny Nom lui répond. |
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A geometric series |
2018-03-13 |
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nathi pose la question : Hi I am really struggling with this question please help !!!!
a pohutukawa tree is 86 centimetres when it is planted. in the first year after it is planted , the tree grows 42 centimetres in height.Each year the tree grows in height by 95% of the growth of the previous year.
assume that the growth in height of the pohutukawa tree can be modelled by a geometric sequence.
A)find the height of the tree 5 years after it is planted and figure out the maximum height the pohutukawa tree is expected to reach in centimetres.
The maximum height part is not answered. Penny Nom lui répond. |
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The growth of a tree |
2014-02-16 |
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Emily pose la question : If a tree is 10 ft tall after 2 years and 25 ft tall after 5 yrs , find the rate of change of growth
Of the tree if y is the height in ft and x is the number of years. Penny Nom lui répond. |
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A coin toss game |
2011-08-29 |
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Aniish pose la question : A and B alternately toss a coin.The first one to turn up a head wins.If no more than 5
tosses each are allowed for a single game,find the probability that the person who tosses
first will win the game?What are the odd's against A losing if she goes first? Penny Nom lui répond. |
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An imaginary infinite geometric tree |
2011-02-18 |
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Elise pose la question : An imaginary infinite geometric tree grows 1m the first day.
2nd day 2 branches and right angles to each other and each 0.5 m long.
3rd day two new branches at ends of each of previous days' 2 branches, again at right angles, and only .25m long each.
And so on, infinitely.
Q: Use relationships of right-angled triangles and high school level knowledge of geometric series to show
the tree height is limited to (4 + sqrt2)/3 m and width to (2(sqrt2 + 1))/3 m. Robert Dawson lui répond. |
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Geometry in the Woods |
2010-06-16 |
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cleo pose la question : what geometric ideas can you find in the woods Walter Whiteley lui répond. |
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A probability tree |
2010-05-20 |
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Sandy pose la question : Children’s meals are being prepared for a large gathering. There is an equal number of chicken, hamburger, and fish meals. Each meal comes with a toy: a ball, a parachute toy, or a Frisbee. There are twice as many balls as Frisbees and an equal number of parachutes and Frisbees.
Use a probability tree to show the sample space and determine the probability that a meal consists of chicken or fish and comes with a ball as a toy. Penny Nom lui répond. |
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Rolling a six on the sixth roll |
2009-05-04 |
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Scott pose la question : What are the odds of rolling a die 6 times in a row and rolling a 6 only on the 6th try, but not any other time? And how is this calculated? Harley Weston lui répond. |
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Ranking 6 players from 49 |
2009-03-24 |
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liz pose la question : My daughter is having problems with this question,
if you had to match 6 players in the correct order for most popular outfielder from a pool of professional players numbered 1 through 49 , how many possibilities are there? Penny Nom lui répond. |
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Will Juanita be late for class? |
2009-01-28 |
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safdar pose la question : juanita bumps into tory in the hallway between period 1 and 2,there is a 45% chance that she will be late for class.if she does not bump into tory, she will make it to class on time. there is a 25% chance that juanita will bump into tory. what is the probability that she will be late on any given day. be sure to introduce your events for this question and show the appropriate formula given the events. Penny Nom lui répond. |
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Choosing light bulbs from a box |
2008-11-14 |
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Annie pose la question : A box of light bulbs contains 3 bulbs, two bulbs are defective.
What is the probability of choosing a non-defective bulb and a defective bulb in 2 draws?
What is the probability of choosing 3 defective bulbs followed by a non defective bulb?
What is the probability of choosing first 2 non defective bulbs followed by a defective bulb? Penny Nom lui répond. |
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The height of a tree |
2008-09-09 |
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danice pose la question : At a certain time of day, the angle of elevation of the sun is 30°. A tree has a shadow that is 25 feet long. Find the height of the tree to the nearest foot. Penny Nom lui répond. |
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Microwave ovens and probability |
2008-09-04 |
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Vi pose la question : A microwave oven manufacturer claims that only 10% of the ovens it makes will need repair in the first year. Suppose three recent customers are independently chosen.
a. If the manufacturer is correct, what is the probability that at least two of the three ovens will need repair in the first year?
b. If at least two of the three customers' ovens need repair in the first year, what inference may be made about the manufacturer's claim? Harley Weston lui répond. |
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Drawing blocks from a box |
2008-02-11 |
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Inez pose la question : A box contains 3 red blocks and 1 green block. A block is chosen without looking and not put back. Then another block is chosen. What are the possible outcomes? Penny Nom lui répond. |
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Conditional probability |
2008-01-14 |
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Sara pose la question : Hello!
Ian has a photocopier in his office. If the photocopier is working on a certain
day then the probability that it will be working the next day is 0.9.
If the photocopier is not working on a certain day then the probability that
it will not be working the next day is 0.3.
The photocopier is not working on Monday.
(a) Calculate the probability that it will be working on Tuesday and Wednesday.
(b) Calculate the probability that it will not be working on Wednesday.
Could you please draw a tree diagram for this problem. Penny Nom lui répond. |
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Related rates - tree growth |
2007-12-09 |
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Christy pose la question : How do I go about answering this question, I know I have to find dv/dt, but I'm not sure how to start.
The volume of a certain tree is given by V= 1/12pie C^2h where C is the circumference of the tree at the ground level and h is the height of the tree. If C=5feet and growing at the rate of 0.2feet per yer, and if h=22feet and is growing at 4 feet per year, find the rate of growth of the volume, V. Stephen La Rocque and Harley Weston lui répond. |
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Related Rates (streetlamp and shadow) |
2007-11-09 |
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Casey pose la question : A street light is mounted at the top of a 15ft pole. A man 6ft tall walks away from the pole at a rate of 5ft per second. How fast is the tip of his shadow moving when he is 40ft from the pole? Stephen La Rocque and Penny Nom lui répond. |
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Probability tree - two switches failing |
2007-06-05 |
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Maura pose la question : draw a probability to show the outcomes of two new switches (a) of both switches being faulty (b)both switches are not faulty (c) that one switch is faulty. The failure rate is 1/10. Stephen La Rocque lui répond. |
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Probability that a restaurant will succeed |
2007-05-23 |
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Cookie pose la question : You wish to open a new restaurant and are considering locations in Toronto and Hamilton, but only one location will actually become available. If it is built in Toronto, the restaurant stands an 80% chance of successfully surviving its first year. However, if it is built in Hamilton, its chance of survival falls to 65%. It is estimated that the chance of Hamilton being available is 60% and Toronto being available is 40%. Find the probability that the restaurant will :
a) survive its first year
b) be built in Toronto and survive its first year
c) be built in Hamilton, given that it survived its first year
d) not survive its first year, given that it is built in Toronto
Thanks Penny Nom lui répond. |
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Probability tree |
2007-05-19 |
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Patrick pose la question : My question involves a video game called Guild Wars. In the game you can have modifications(mods) on items. One such mod is that you have a 20% chance to halve the casting time of a spell. You can have 2 of these mods available to you. Now, it is to my understaning that combined, you would have a 32% chance to halve the casting time and a 4% chance to quarter the casting time. Is this correct? Stephen La Rocque lui répond. |
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Choosing a bicycle |
2007-03-28 |
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Jackie pose la question : A specific brand of bike comes in two frames, for males or females. Each frame comes in a choice of two colors, red and blue, and with a choice of three seats, soft, medium, and hard.
a) Use the counting principle to determine the number of different arrangements of bicycles that are possible.
b) Construct a tree diagram illustrating all the different arrangements of bicycles that are possible. c) List the sample space. Penny Nom lui répond. |
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A person is given 3 true or false questions |
2006-05-11 |
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Larry pose la question : A person is given 3 true or false questions. They have no idea of the answers. What is the probability of the person getting them all correct? Could you show me a tree for this. Penny Nom lui répond. |
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Planting trees |
2004-11-15 |
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Heather pose la question : Design a plan of how it would be possible to plant 10 trees in 5 rows, and have 4 trees in each row. Penny Nom lui répond. |
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Tennis balls and probability |
2004-11-01 |
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Jeremy pose la question : I have a hopper of tennis balls that contains 25 new tennis balls and 10 old tennis balls. In the hopper the tennis balls are mixed up randomly. If i take one ball out of the hopper and hit it and then put it back and then take another ball out of the hopper and hit it and put it back, what is the probability that i hit two new tennis balls? Also a tennis ball becomes old after being hit just once. Penny Nom lui répond. |
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Selecting balls from a golf bag |
2004-02-21 |
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A student pose la question : There are 5 white and 5 yellow balls in a golf bag. Two are selected randomly, and simultaneously. What is the probability that the first one or the second one will be white? Penny Nom lui répond. |
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Probabilities and olivies |
2004-02-14 |
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Annetta pose la question : A bowl contains five green olives and eight black ones. Wilma sticks a fork into a bowl and brings out two olives. What is the probability that she gets one green and one black olive? Harley Weston lui répond. |
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Trees |
2003-10-28 |
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Ali pose la question : Is there any formula for counting the number of trees (graphs)? Denis Hanson lui répond. |
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Sesame Street on Stage |
2003-06-25 |
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Christie pose la question : Sesame Street on Stage has different ticket prices for adults and for children under 6. Beth and her two children, ages 3 and 4, paid $15 to gain entrance, while Jamie and John Jacobs and their 2-year old daughter got in for $19.50. What is the ticket price for adults? Penny Nom lui répond. |
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Chopping trees |
2003-04-19 |
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Tamara pose la question :
The master needs some of the trees (twenty, to be exact) at the back of his spooky old mansion cleared to make way for a new evil laboratory, so he decides to send some his slaves to do the work for him. He initially sends out four of his men, armed with axes, to chop the trees down. Due to the fact he is very impatient, every ten minutes he sends out another man to help with the work. Assuming that it takes one man 30 minutes to chop down 1/3 of a tree, how long till all twenty trees are chopped down? Penny Nom lui répond. |
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How many trees were planted in March? |
2002-10-20 |
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Allison pose la question : The number of trees planted by the Alpine Nursery in April was 3 more than twice the number of trees planted in March. If 71 trees were planted in april, write and solve an equation to find how many trees were planted in March. Penny Nom lui répond. |
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Tree diagrams |
2002-10-12 |
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Denean pose la question :
- For lunch, students can choose juice or milk; hamburger or pizza; and a banana or apple. How many lunch combinations can the students make?
- In an experiment, Monty can use paper towels or cloth. He can choose red, green, or yellow food coloring. How many combinations are there?
Penny Nom lui répond. |
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A probability tree |
2002-05-04 |
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A student pose la question : Karl and Naomi roll three dice. Karl gives $10 to Naomi if the number 5 turns up once, twice or three times. Naomi gives Karl $3 in all other cases. A) construct the probability tree for this situation.
B) Does Karl have an advantage in this game? Justify your answer. My problem is I am unfamiliar on how to draw this probability tree and seem to be having a lot of difficulties, when you have a chance please answer this math problem and get back to me with the results. Penny Nom lui répond. |
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All of the Christmas trees are fifty-five percent off. |
2002-01-08 |
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A teacher pose la question : All of the Christmas trees are fifty-five percent off. Madison bought a tree and paid $103.50. Assuming no tax, what was the original price of the tree? Penny Nom lui répond. |
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Maple trees and pine trees |
2002-01-06 |
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A student pose la question : A team of scientists found that in a forest there was four maple trees for every nine pine trees.How many maple were there if they counted 45 more pine than maples? Penny Nom lui répond. |
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Is the tree a pine tree? |
2001-10-27 |
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Kate pose la question : Suppose Stock Brokers tell the truth 2/5 of the time, and 1/3 of the trees in a given forest are Pine. If 4 Stock Brokers say that a certain tree in that forest is Pine, what is the probability that the tree is indeed a Pine tree? Penny Nom lui répond. |
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Genealogy |
2001-03-22 |
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Brian pose la question : In considering tracing genealogy the problem of a large and growing number of direct (grandparent) ancestors arose. Since the number of grandparents in any given generation doubles, for a person born in 2000 and assuming 25 year generations, in the year 1000 that person would have over one trillion direct ancestors in that year alone. Since estimates I have read place the total world population in 1000 at 250-300 million, the one trillion figure cannot be correct. I must be missing something in my calculations. Can you help provide the answer? While I am unlikely to be able to trace back to 1000, there is reason to believe 1250 is possible. Even in that year there would exist over one billion direct ancestors. That is certainly rather daunting and unlikely to be achieved if correct. Penny Nom lui répond. |
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How tall is the tree? |
2001-03-02 |
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Ronda pose la question : a tree's shadow is 42 ft. long. There is a stop sign that is right next to it and it is 18 ft. tall and it's shadow is 12 ft. long. How tall is the tree? Penny Nom lui répond. |
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False Positives |
2000-10-29 |
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James pose la question : A rare disease infected 1 in 1000 people in the population. A test for the disease is accurate 99% of the time when given to an infected person and also when given to a heathy person. - Fill out a two-tier tree diagram and find the probability of the false positive(i.e the conditional probabily of being healty even when tested postive by the test) Comment on the result?
- ...
Penny Nom lui répond. |
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Factoring, primes, GCF and LCM |
2000-02-27 |
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Ruth Kroek pose la question : My son is in grade seven, he has to do a Factoring Booklet the areas covered are: - Prime #'s
- Composite #'s
- Rainbow Factoring
- Finding Multiples (consecutive multiples)
- Finding GCF of 2-3 numbers uning Rainbow factoring
- Finding LCM of 2 numbers using consecutive multiples
- prime factor trees
- prime factor ladders
- finding GCF of 2 numbers using Prime number Method
Although his text 'Math Power' gives some information, we are at a loss .. Penny Nom lui répond. |
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Diagramming Powers |
1997-10-15 |
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David Fill pose la question : I am a teacher in Massachusettes. We have been diagramming numbers such as two to the third (a 3-D cube). One of my students asked me how you would diagram two to the fourth. I have searched through all of my teachers books and cannot seem to find the answer to this question. Is there a way to diagram this? If there is, how would you do this? Your help would be greatly appreciated. Penny Nom lui répond. |
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