Question

Jamarcus has twenty-one coins is his piggy bank, all of which are either dimes or quarters. If Jamarcus has $4.20 in total, how many of each coin does he have?

Answer 1

16 quarters 2 dimes

Explanation:

16 quarters is 4 dollars

2 dimes is 20 cents

Answer 2

Explanation:

If D is number of dimes and Q is number of quarters:

D + Q = 21

10D + 25Q = 420

Solve the system of equations through either substitution or elimination.

10D + 25(21 - D) = 420

10D + 525 - 25D = 420

105 = 15D

D = 7

Q = 14

There are 7 dimes and 14 quarters.