Question 320122
The box currently contains 44 coins, consisting of pennies, dimes, and quarters.
 The number of pennies is equal to the number of dimes, and the total value is $4.37.
 How many of each denomination of coin does he have in the box?
:
Write an equation for each statement:
:
"box currently contains 44 coins,"
p + d + q = 44 
:
"The number of pennies is equal to the number of dimes,"
p = d
:
"the total value is $4.37."
.01p + .10d + .25q = 4.37
:
Substitute d for p in the total coin equation
d + d + q = 44
2d + q = 44
:
Substitute d for p in the total value equation
.01d + .10d + .25q = 4.37
.11d + .25q = 4.37
:
Now we have two equation for two unknowns
:
Multiply the above equation by 4, subtract from the two unknown coin equation
2.0d + 1q = 44
.44d + 1q = 17.48
------------------subtraction eliminates q, find d
1.56d = 26.52
d = {{{26.52/1.56}}}
d = 17 dimes
we know p = d, therefore:
17 pennies
:
:
I'll let you find the number of quarters




 How many of each denomination of coin does he have in the box?