Question 184065
Philip has 10 coins in his pocket. Philip has the same number of pennies as
 quarters and the same number of dimes as nickels. He also has one more nickel
 than he does pennies. If he has 97 cents, how many coins of each type does he have?
:
let p, n, d, q = no. of pennies, nickels, dimes and quarter respectively
:
Write an equation for each statement:
:
"Philip has 10 coins in his pocket."
p + n + d + q = 10
:
" Philip has the same number of pennies as quarters"
p = q
:
" and the same number of dimes as nickels."
d = n
:
"He also has one more nickel than he does pennies."
n = (p + 1)
:
" If he has 97 cents,"
1p + 5n + 10d + 25q = 97
:
 how many coins of each type does he have?
:
Using the given equations, replace p with q, and d with n in the 1st equation
q + n + n + q = 10
2n + 2q = 10
simplify, divide by 2
n + q = 5
n = (5-q) good for substitution
:
Do the same in the total value equation
1q + 5n + 10n + 25q = 97
15n + 26q = 97
:
Substitute (5-q) for n
15(5-q) + 26q = 97
75 - 15q + 26q = 97
11q = 97 - 75
11q = 22
q = {{{22/11}}}
q = 2 quarters
:
we know p = q, therefore
p = 2 pennies
:
we also know n = p + 1, therefore
n = 3 nickels
:
we know d = n, therefore
d = 3 dimes
:
Check solution, in total coin equation
2 + 3 + 3 + 2 = 10
:
You can check solution in total value equation
1q + 5n + 10n + 25q =