Question

a girl spent 2/5s of her money on a book and 2/3s of what she had left on a folder. she then had $11 left. How much money did she start with?

Answer 1

Find amount of money before leaving on a folder
money on folder : money before leaving on a folder = 2 : 3
the ratio of money she brought = 3 - 2 = 1

money before leaving on a folder = 3/1 x 11
money before leaving on a folder = $33

Find amount of initial money
money spent : initial money = 2 : 5
the ratio of the left money = 5 - 2 = 3

amount of initial money = 5/3 × 33
amount of initial money = $55

Answer 2

she started with exactly 28