Answers:
6 quarters
2 dimes
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Work Shown:
d = number of dimes
q = number of quarters
q = d+4 since she has 4 more quarters than dimes
$1.70 = 170 cents
10d = value of all the dimes in cents
25q = value of all the quarters in cents
10d+25q = total value of all the coins in cents
10d+25q = 170
10d+25( q ) = 170
10d+25( d+4 ) = 170 .... plug in q = d+4
10d+25d+100 = 170 .... distribute
35d+100 = 170
35d = 170-100 ..... subtract 100 from both sides
35d = 70
d = 70/35 ... divide both sides by 35
d = 2
He has 2 dimes
q = d+4
q = 2+4
q = 6
He also has 6 quarters
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Check:
1 dime = 10 cents
2 dimes = 20 cents ..... multiply both sides by 2
1 quarter = 25 cents
6 quarters = 150 cents ..... multiply both sides by 6
(2 dimes) + (6 quarters) = (20 cents) + (150 cents) = 170 cents
This confirms the answers.
