SOLUTION: the question is:
Your piggy bank has a total of 47 coins in it; some are dimes and some are nickels. If you have a total of $3.95, how many nickels and how many dimes do you hav
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Your piggy bank has a total of 47 coins in it; some are dimes and some are nickels. If you have a total of $3.95, how many nickels and how many dimes do you hav
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Question 344714: the question is:
Your piggy bank has a total of 47 coins in it; some are dimes and some are nickels. If you have a total of $3.95, how many nickels and how many dimes do you have? Show all of your work to receive full credit.
I tried for at least 20 min and only got this,
d+n=47
-d -d
.10d+.05n=3.95
n=d+47
.10d+.05(d+47)=3.95
.10d+.05d+2.35=3.95
.15d+2.35=3.95
-2.35 -2.35
.15d=1.6
/.15 /.15
d=10.66 Found 2 solutions by ankor@dixie-net.com, scott8148:Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Your piggy bank has a total of 47 coins in it; some are dimes and some are nickels. If you have a total of $3.95, how many nickels and how many dimes do you have? Show all of your work to receive full credit.
I tried for at least 20 min and only got this,
:
d+n=47
:
.10d+.05n=3.95
:
n=d+47; this is wrong, it should be
n = (47-d)
so you have:
.10d+.05(47-d)=3.95
.10d + 2.35 - .05d = 3.95
.10d - .05d = 3.95 - 2.35
.05d = 1.60
d =
d = 32 dimes
then
n = 47 - 32
n = 15 nickels
:
Check this
.05(15) + .10(32) =
.75 + 3.20 = 3.95
;
You had the right idea, but a fatal mistake right at the beginning.
