 |
|
|
|
|
|
|
|
|
A storage box with a slanted roof |
2012-02-13 |
|
Sophia pose la question :
Hi!
I have another problem.
The diagram shows a side view of a box which is used to store small logs of
wood for burning in a fire place. The slopping lid has an overhand of 15cm.
a) Calculate the total length of the slopping lid to the nearest cm.
b) When the lid is open above ground will the end of the lid be?
P.S. Please see attached.
Penny Nom lui répond. |
|
|
|
|
|
|
Simplify the expression |
2012-02-12 |
|
Christy pose la question :
Hi guys, ok so I'm having problems with solving this equation since it's been so long I've done precal.
I have to find critical points so I have to find the derivative first. This is what I've done so far
s(t)= (t-6)^4 * (t+1)^2
t'= 4(t-6)^3*(1)*(t+1)^2+ 2(t+1)(1)*(t-6)^4
so this is where I got stuck, which is the algebra part. How can I simplify this to get the answer to figure out the critical points.
Penny Nom lui répond. |
|
|
|
|
|
|
A 3 to 1 ratio of girls to boys |
2012-02-12 |
|
amanda pose la question :
At a recent school dance it was observed that there was a 3 to 1 ratio of girls to boys. If 204 students attended the dance, how many boys, and how many girls were there?
Penny Nom lui répond. |
|
|
|
|
|
|
A circle and a chord |
2012-02-11 |
|
Sophia pose la question :
The diagram shows a circle with a chord that is 10cm long. The middle of the chord is 12cm from the centre of the circle. Calculate the radius.
Chord length is 10cm.
The distance from the centre to chord is 12 cm.
Penny Nom lui répond. |
|
|
|
|
|
|
Can the result of the calculation be 2? |
2012-02-09 |
|
Thomas pose la question :
You have the digits 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9 in a random order side by side and put randomly between two digits a colon, so that a division comes into existence. Can the result of the calculation be 2?
Robert Dawson and Chris Fisher lui répond. |
|
|
|
|
|
|
Litres in a box |
2012-02-09 |
|
vicky pose la question :
how much litre water can be filled in a box of 12 inches *24 inches *12inches
Penny Nom lui répond. |
|
|
|
|
|
|
Two circles |
2012-02-08 |
|
crisfe pose la question :
find the point where the common cord of the circles x2+y2=25, x2+y2-12x-6y+35=0 process there line centers. what point they intercepts?
Penny Nom lui répond. |
|
|
|
|
|
|
A tree growth modelled by a geometric series |
2012-02-08 |
|
Steph 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
Penny Nom lui répond. |
|
|
|
|
|
|
Wallpapering a room |
2012-02-08 |
|
jimmy pose la question :
Ms. Frank is going to
wallpaper a living room with dimensions
24 feet long, 18 feet wide, and 8 feet
high. What surface area does Ms. Frank
plan to wallpaper?
Penny Nom lui répond. |
|
|
|
|
|
|
The curvature of the earth |
2012-02-08 |
|
sean pose la question :
Question from sean, a student:
Two people 1.8 metres tall walk directly away from each other until they can no longer see each other (due to the curvature of the earth, which has a radius of about 6378 km).
A) Find a function relating the height of two identical objects with the distance between them using the scenario above as an example.
B) Sketch this function (you may use Graphmatica if you wish). Over what domain and range does the function exist?
C) Describe this relation in practical terms.
Harley Weston lui répond. |
|
|
|
|
|
|
A road around a garden |
2012-02-07 |
|
Manu pose la question :
Inside a square garden of side 158m, a road 4m wide is built all around. What is the area of the remaining part of the garden?
Penny Nom lui répond. |
|
|
|
|
|
|
The volume of a round tube |
2012-02-07 |
|
I.C pose la question :
I need to find out how long a 10" round tube needs to be in order for there to be .95 cubic feet of air space
Harley Weston lui répond. |
|
|
|
|
|
|
38/50 as a percent |
2012-02-06 |
|
2 pose la question :
38/50 in a percent
Penny Nom lui répond. |
|
|
|
|
|
|
Expressing 0.5% |
2012-02-06 |
|
Kenneth pose la question :
Hello:
It is correct to express 0.5% as 5 tenths of one percent.
Is it also correct to express 0.5% as 5 tenths of one-hundred percentage points or 5 tenths of one percentage point?
I think it would be 5 tenths of one percentage point because 5 tenths of one-hundred percentage points would be 50 percentage points, but I'm not sure.
I thank you for your reply.
Penny Nom lui répond. |
|
|
|
|
|
|
Notation for the second derivative |
2012-02-06 |
|
Shafira pose la question :
In all math textbooks, it is written that d/dx ( d/dx) (y)= d2y/dx2. Why do they write it as d2y/dx2, not as d2y/d2x2?
Robert Dawson lui répond. |
|
|
