196k views
5 votes
I have $9.45 in quarters and dimes in my pocket. The number of dimes is 18 less than twice the number of quarters. How many of each coin are there?

User Tounaobun
by
4.8k points

1 Answer

2 votes

Answer:

32 dimes and 25 quarters

Step-by-step explanation:

let Q = quarters and D = dimes

2Q - 18 = D

25Q + 10D = 945

we can replace D

25Q + 10(2Q - 18) = 945

25Q + 20Q -180 = 945

45Q = 1,125

Q = 1,125 / 45 = 25

D = (2 x 25) - 18 = 50 - 18 = 32

to check the answer:

(25 x 25) + (32 x 10) = 625 + 320 = 945

User Raphi
by
5.1k points