







A footballer angle 
20180214 

Kim pose la question : Two goal posts are 8m apart. A footballer is 34m from one post and 38m from the other. Within what angle must he kick the ball if he is to score a goal. Penny Nom lui répond. 





What is the speed of the skateboarder? 
20180213 

Zack pose la question : It takes a skateboarder 20 minutes to get to school, which is 6 km from home. What is the speed of the skateboarder? Penny Nom lui répond. 





Solar cells 
20180212 

karla pose la question : Solar (photovoltaic) cells convert sunlight directly into electricity. If solar cells were 100% efficient, they would generate about 1000 watts of power per square meter of surface area when exposed to direct sunlight. With lower efficiency, they generate proportionally less power. For example, 10% efficient cells generate 100 watts of power in direct sunlight. Suppose you want to supply 22 kilowattss of power to a house by putting solar panels on its roof. For solar cells with the average power of 49 watts per square meter of solar panels, how many square meters of solar panels would you need? Assume you can make use of the average power from the solar cells Penny Nom lui répond. 





Related rates 
20180211 

angelo pose la question : hi admin please help me answer this question. thank you!
At a certain instant of time, the angle A of a triangle ABC is 60 degrees and increasing at the rate of 5degrees per second, the side AB is 10cm and increasing at the rate of 1cm per second, and side AC is 16cm and decreasing at the rate of 1/2 cm per second. Find the rate of change of side AB? Penny Nom lui répond. 





Water in a cone 
20180210 

Shuvo pose la question : The diagram shows a vertical crosssection of a container in the form
of an inverted cone of height 60 cm and base radius 20 cm. The circular
base is held horizontal and uppermost. Water is pursed into the
container at a constant rate of 40 cm3/s.
Show that, when the depth of water in the container is x cm, the
volume of the water in the container is (πx^3)/27 cm3.
Find the rate of increase of "x" at the instant when "x" = 2. Penny Nom lui répond. 





3 yards 6 inches times 7 
20180208 

Tamara pose la question : 3 yards 6 inches × 7 Penny Nom lui répond. 





A parallelogram, a rhombus and a rectangle 
20180207 

Sambo pose la question : what do parallelogram, rhombus and rectangle have in common? Penny Nom lui répond. 





The wholesale price given the retail price and the markup 
20180207 

Matthew pose la question : Retail $99
Markup is 80%
What is the equation to find the original (wholesale) price (55)?
thanks Penny Nom lui répond. 





Adding two negatives 
20180204 

Pinasshakoane pose la question : (23)+(3) Penny Nom lui répond. 





A question about perfect squares 
20180204 

Jolyn pose la question : Find the smallest possible value of a whole number m if 648x m is a perfect square Penny Nom lui répond. 





The code on a new phone 
20180202 

Maria pose la question : Hi 
My husband gave me a new Samsung Galaxy mobile for out anniversaire gift. He set me a challenge which I have to solve before I can use the Phone. He has set the pin code with numbers 4, 7 and 0 and created a four digit code with the said numbers. Is there a way I can somehow list all possible combinations and try them all? Thanks! Penny Nom lui répond. 





Similar rectangles 
20180131 

Kathy pose la question : A rectangular picture frame is 14 inches long and 4 inches wide. Which dimensions could a similar picture frame have.
8 L X 21 W
35 L X 15 W
49 L X 14 W
7 L X 3 W Penny Nom lui répond. 





Positive and negative values of a function 
20180130 

Grayson pose la question : f(x)=x^6x^4
Interval: ( negative infinity, negative one )
Test Value: negative two
Function Value f(x): positive forty eight
Interval: ( negative one, zero )
Test Value: negative one
Function Value f(x): zero
Interval: ( zero, positive one )
Test Value: positive one
Function Value f(x): zero
Interval: ( positive one, positive infinity )
Test Value: positive two
Function Value f(x): positive forty eight
What is the sign of f(x) for each Interval? Penny Nom lui répond. 





Pricing a piece of plate steel 
20180129 

Simo pose la question : I have a piece of plate that is 2500mm x 8000mm x 20mm thick and costs $7693.00
what is the formula to work out what 1000mm x 1000mm is worth? Penny Nom lui répond. 





Simplify 1/2^i 
20180128 

Deepak pose la question : How do I simplify this complex equation:
z=1/(2^i) Penny Nom lui répond. 

