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4 votes
Miguel has one dollar in change. He has twice as many nickels as dimes. He has 14 more pennies than quarters. What coins does he have?

User JCB
by
6.9k points

1 Answer

6 votes
d=dimes
n=niclkes
p=pennies
q=quarters

1 dollar (100 cents)
2 times as many nickles as dimes
n=2d

14 more pennies than quarters
p+14=q

and total is 1 dollar so
25q+10d+5n+p=100
ok so we must use logic
the max number of quarters in a dolar is 4
but there are pennies so max is 3
so q=1,2, or 3
therefor p=15,16 or, 17

also, the rest of te coins are only multipules of 5 so the sum amount of pennies and quartes must add to a multiplule of 5

if q=1 and p=15, total is 40 cents
if q=2 and p=16, total is 66 cents
if q=3 and p=17, total is 92 cents
only 40 cents is a multiplule of 10

1 quarter and 15 pennies
now we are having
40 cents is pennies and quartesrs
therfor 100-40=60 cents is nickles and dimes
60=5n+10d
n=2d
sub
60=5(2d)+10d
60=10d+10d
60=20d
divide both sides by 20
3=d
sub
n=2d
n=2(3)
n=6

6 nickles
3 dimes




answer is
1 quarter
3 dimes
6 nickles
15 pennies
User Mehandi Hassan
by
5.8k points
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