64% of x is 140 please help me right away and solve me x!

A3x4x5 rectangular cuboid (e. g. a brick) is painted blue and cut into 1x1 cubes. what is the expected value for the painted sides of a randomly selected cube?

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

Eric drove 275 miles in 5 hours. at the same rate how long would it take him to drive 495 miles?