How to use properties to find the sum or product for 8×51

The following frequency table relates the weekly sales of bicycles at a given store over a 42-week period. value01234567frequency367108521(a) in how many weeks were at least 2 bikes sold? (b) in how many weeks were at least 5 bikes sold? (c) in how many weeks were an even number of bikes sold?

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

Which of the following shows the length of the third side, in inches, of the triangle below