Sandra spent one-fifth pf her money and loaned one-third of the remainder to her brother Sam. She then had $24. How much money did she have at first?

Answer 1

m - m/5 - (4m/5)/3 = 24
m - m/5 - 4m/15 = 24
8m/15 = 24
m = 24(15/8) = 45

check:
started with 45
spent 9, leaving 36
lent 12, leaving 24