Somebody can estimate the length of a book by using a ruler and rounding it to the nearest whole number.
This is middle school??? AinT no way
Volume of the pipe = πr^2l
Wrong measure = π x (2)^2 x l = 4πl
Correct measure = π x (2 - 2(1/8))^2 x l = 49/16πl
error = 4πl - 49/16πl = 15/16πl
% error = ((15/16πl) / 49/16πl) x 100% = 30.6%
You have to find the cos of angle A, so use the Pythagorean equation and trig laws to find the other side of the triangle created by angle A. 3^2 + x^2 = 5^2. x=4. This means cos(A) = 4/5). Make both cos (A) and cos (B) have equal denominators, and add. 148/185 + 60/185 = 208/185. This answer is correct, though it doesn’t appear to be any of the answers you wrote, so either those answers are wrong or you wrote something incorrectly in the problem.
