SOLUTION: jack and betty have 28 coins that are nickels and dimes if the value of the coins is $1.95 how many coins of each type do they have

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Question 279354: jack and betty have 28 coins that are nickels and dimes if the value of the coins is $1.95 how many coins of each type do they have

Found 2 solutions by josmiceli, JBarnum:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let d = number of dimes
Let n = number of nickels
given:
10d+%2B+5n+=+195
n+%2B+d+=+28
----------------
d+=+28+-+n
and
10%2A%2828+-+n%29+%2B+5n+=+195
280++-+10n+%2B+5n+=+195
5n+=+280+-+195
5n+=+85
n=+17
and
n+%2B+d+=+28
17+%2B+d+=+28
d+=+11
They have 17 nickels and 11 dimes
check answer:
10d+%2B+5n+=+195
10%2A11+%2B+5%2A17+=+195
110+%2B+85+=+195
195+=+195
OK

Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
nickel=.05 N= amount of nikels
dime=.10 D= amount of dimes
N+D=28
.05N+.10D=1.95
u can either use substitution or elimination method. im going to use elimination method
N%2BD=28multiply this line by -.10 to get:
-.10N-.10D=-2.8
.05N%2B.10D=1.95 add these to equations together
-.05N=-.85divide
N=17
N+D=28
17%2BD=28
D=11
check
.05N+.10D=1.95
.05%2817%29%2B.10%2811%29=1.95
.85%2B1.10=1.95
1.95=1.95 correct