Justin is exchanging dollars for rolls of quarters and rolls of dimes at

Justin is exchanging dollars for rolls of quarters and rolls of dimes at a bank. Each roll of quarters has a value of $10 and each roll of dimes has a value of $5. He exchanges $90 and receives 11 rolls of coins. How many of each type of roll of coins did he receive?

2 months ago

Solution 1

Guest Guest #4129
2 months ago


Justin got 7 rolls of quarters and 4 rolls of dimes.

Step-by-step explanation:

Let the roll of quarters be x

Let the rolls of dimes be y

As total money received is $90, the equation becomes;

10x+5y=90    .....(1)

And he got 11 roll of coins, so equation becomes;

x+y=11 or x=11-y    .... (2)

Substituting the value of x from (2) in (1)


=> 110-10y+5y=90

=> -5y=-110+90

=> -5y=-20

So, y = 4

As x=11-y

So, x=11-4

x = 7

Hence, Justin got 7 rolls of quarters and 4 rolls of dimes.

Solution 2

Guest Guest #4130
2 months ago
Well, it really depends but it could be 9 rolls of quarters, 5 rolls of quarters and 8 rolls of dimes, 4 rolls of quarters and 10 rolls of dimes, 3 rolls of quarters and 12 rolls of dimes, etc.

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