







A circle in a square 
20200402 

From Sabra: Hello, I have twins in the 7th grade that are learning how to find
circumference of circles. I am struggling with figuring out how to
help my children to find the answer to this question:
Tye has a square piece of yellow felt that has an area of 81
square inches. She wants to cut the largest circle possible from the
material to create a sun for her art project. What is the area of the felt
circle? Use 3.14 for pi. Round to the nearest hundredth if necessary.
I wasn't sure if I am to find the area of the circle through finding the
area of the square or what steps we needed to follow to find the
answer. Once I can see how one is worked out stepbystep, I
usually can help them along with questions that are similar. Answered by Penny Nom. 





A circle of circumference 4*pi*r 
20180319 

From Ankith: If the circumference of a circle is 4*pi*r, what is its area?
i) 4*pi*r^2
ii) 2*pi*r^2
iii)3*pi*r^2
iv) pi*r^2 Answered by Penny Nom. 





A circle formed from bending a wire 
20161016 

From Deszaree: The same piece of a wire is bent to form a circle
calculate:
a, the radius of the circle
b, the area of the circle Answered by Penny Nom. 





The area of a circle in terms of the circumference 
20141104 

From Sarah: How do you find the area of a circle if you already have the circumference?
There was one answer to this question already but it didn't make sense to
me, because they rounded up pi which you can't do so the answer is
incorrect. thanks Answered by Penny Nom. 





A reel of cotton thread 
20120605 

From Grace: 91 meters of cotton goes round the cotton reel. About how many times does the cotton go round the reel?
Give your answer to the nearest ten.
(The Diameter of the cylinder is 3cm) Answered by Penny Nom. 

