SOLUTION: Tim had $5.03 in quarters, nickels, dimes, pennies, and half-dollars in a desk drawer. He has five more nickels than quarters, the number of pennies is two-thirds the number of nic

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Tim had $5.03 in quarters, nickels, dimes, pennies, and half-dollars in a desk drawer. He has five more nickels than quarters, the number of pennies is two-thirds the number of nic      Log On


   



Question 219001: Tim had $5.03 in quarters, nickels, dimes, pennies, and half-dollars in a desk drawer. He has five more nickels than quarters, the number of pennies is two-thirds the number of nickles, there are half as many dimes as nickels.How many coins of each type does he have?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let q = number of quarters he has
Let d = number of dimes he has
Let n = number of nickels he has
Let p = number of pennies he has
Let h = number of half-dollars he has
Just by looking at the amount of money Tim has,
you can tell a lot about the coins that make it up.
(1) The number of half dollars must be less than
10, since that would leave no room for other coins
(2) He must have at least 3 pennies to get $5.53.
-----------------------------------------------------
given:
(1)n+=+q+%2B+5
(2)p+=+%282%2F3%29%2An
(3)d+=+n%2F2
(4)10d+%2B+5n+%2B+p+%2B+25q+%2B+50h+=+503 (in pennies)
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There are 5 unknowns and only 4 equations, so
it will take some extra work to get the answer
From (1), q+=+n+-+5
Substituting into (4),
10%2A%28n%2F2%29+%2B+5n+%2B+%282%2F3%29%2An+%2B+25%2A%28n-5%29+%2B+50h+=+503
Multiply both sides by 6
30n+%2B+30n+%2B+4n+%2B+150%2A%28n-5%29+%2B+300h+=+3018
64n+%2B+150n+-+750+%2B+300h+=+3018
214n+%2B+300h+=+3768
107n+%2B+150h+=+1884
I need a combination of n and h that
will give me 1884, and h must be 9 or less
--------------------
107%2A1+%2B+150%2A9+=+1457
107%2A2+%2B+150%2A9+=+1564
107%2A3+%2B+150%2A9+=+1671
107%2A4+%2B+150%2A9+=+1778
107%2A5+%2B+150%2A9+=+1885
There can't be 9 half-dollars,
I'll try 8 halfs
107%2A5+%2B+150%2A8+=+1735
107%2A6+%2B+150%2A8+=+1842
Can't be it, increasing n takes me over 1884
107%2A6+%2B+150%2A7+=+1592
107%2A7+%2B+150%2A7+=+1799
Next increase in n takes me over 1884
107%2A8+%2B+150%2A6+=+1756
107%2A9+%2B+150%2A6+=+1863
not it
107%2A10+%2B+150%2A5+=+1820
107%2A12+%2B+150%2A5+=+2034
not it
107%2A12+%2B+150%2A4+=+1884 BINGO
Now I know that
n+=+12
h+=+4
and
p+=+%282%2F3%29%2An
p+=+%282%2F3%29%2A12
p+=+8
and
q+=+n+-+5
q+=+12+-+5
q+=+7
and
d+=+n%2F2
d+=+6
Tim has 8 pennies, 12 nickels, 6 dimes, 7 quarters, and 4 half-dollars
check answer:
(4)10d+%2B+5n+%2B+p+%2B+25q+%2B+50h+=+503
10%2A6+%2B+5%2A12+%2B+1%2A8+%2B+25%2A7+%2B+50%2A4+=+503
60+%2B+60+%2B+8+%2B+175+%2B+200+=+503
503+=+503
OK