math - 5th grade
posted by Sylvie .
I am having difficulty witht the following math:
Question #1 If the area of a circle is 27 sq. in. What is the radius? I am coming up with an answer of 13.5 sq. in. Is that correct? If not, can you show me step by step how to get the answer?
Question #2 If the area of a circle is 108 cm to the second power, what is the radius?
Grade 5, that's pretty tough
The area of a circle is pi times the radius squared, so work it backwards
divide 27 by pi (on calculator) = 8.594
now take the square root of that to get a radius of 2.93 inches.
your answer is in square inches, that makes no sense.
How did you get 13.5 ?
Do the second question the same way as I showed you for the first, you should get 5.863
If your circle is 27 sq in. Here is how you would work it out to find the radius.
A(area)=3.14(pie) times R(radius) times R
27sq in. = 3.14 x R x R=
27sq in/3.14 x R x R=
8.59 sq in x R =
8.59 sq rt= 2.93
So your radius = 2.93
hope this helps
i need help with my home work so whats another name for 3/8? and whats another name for 5/12 and whats another name for 6/10??? thank you
I'm in the 1st grade! no joke! And Wendy the answer is For five tenths is one half!