Question

Sumanta has $175 in $5 and $10 bills in his drawer. The number of $5 bills is three times the number of $10 bills. How many of each are in the drawer?

Answer 1

5x + 10y = 175

x = 3y

15y + 10y = 175

25y = 175

y = 7, so x = 21

21 five-dollar bills, 7 ten-dollar bills