math
posted by abraham on .
using rounding or compatible numbers,which numbers would you choose to estimate the exact product of 25 times 25.

I don't see how one would get an exact answer by rounding.
Try using this:
(a c)(b +c) = ab + (ab)c  c^2
with a = 30, b = 20 and c = 5
25 * 25 = 600 + 50  25 = 625 
I would round by doing 20 * 30, since 25 is exactly halfway between. 2 * 3 = 6, put 2 0's on the end..600

"Estimating the exact product" seems like an oxymoron to me.

955