Mark earned $40 mowing lawns last week. he spent 3/5 of his money on two cds. how much did he spend on these two cds?

Find out 1/5 of 40
40÷5＝$8
There's three 1/5 in 3/5.
So, 8 × 3 ＝ $24

You can find the area of a rectangle by multiplying the length and height. so multiply 1/2*7/4(which is the simpler version of 1 3/4) and you get 7/8 as your answer.