SOLUTION: A parking meter contains $8.25 in dimes and quarters. If the number of quarters is 9 more than twice the number of dimes, how many of each coin are in the parking meter?

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Question 186117This question is from textbook Algebra 1
: A parking meter contains $8.25 in dimes and quarters. If the number of quarters is 9 more than twice the number of dimes, how many of each coin are in the parking meter? This question is from textbook Algebra 1

Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
d = no. of dimes; q = no. of quarters
:
Write an equation for each statement:
:
A parking meter contains $8.25 in dimes and quarters.
.10d + .25q = 8.25
"
the number of quarters is 9 more than twice the number of dimes,
q = 2d + 9
:
how many of each coin are in the parking meter?
;
Substitute (2d+9) for q in the total$ equation
.10d + .25q = 8.25
.10d + .25(2d+9) = 8.25
.10d + .50d + 2.25 = 8.25
.60d = 8.25 - 2.25
.60d = 6.00
d =
d = 10 dimes
and
q = 2(10) + 9
d = 29 quarters
;
;
Check solution
.10(10) + .25(29) =
1.00 + 7.25 = 8.25