The answer is -6. Thought there is a chance I am wrong. Need an explanation?
81.7%
This is because the area of the inside circle is roughly 18.3% of the big circle. You can get this by finding both of their areas and then dividing the inside circle by the outside one.
Answer:
I certainly am
Step-by-step explanation:
I'm sure you know the formula for Pythagoras Theorem.
The formula is 
C = Your hypotenuse
A + B = The other two adjacent sides.
So you plug in the numbers

And you'll get the answer, which is 56.
The smallest number of pencils and erasers and 1 eraser per pencil so number of pencils and erasers are equal
*GCD( 12;10) = 60
So Philip buy 60÷12=5 packages of erasers
60÷10=6 packaes of pencils