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3 years ago

14

Please help fast!! Katrina has $3.60 worth of nickels and dimes. She has 46 coins in total. How many nickels and dimes does she

have?

1 answer:

Igoryamba3 years ago

6 0

Answer:

20 nickels and 26 dimes

Step-by-step explanation:

She has $3.60 in nickels and dimes
a nickel is $0.05 and a dime is $0.10
let n be the number of nickels and d be the number of dimes
thus the first equation is 3.6 = 0.05n +0.1d
If she has 46 coins then n + d = 46
then n = 46 - d
sub n = 46 - d into 3.6 = 0.05n +0.1d
3.6 = 0.05(46 - d) + 0.1d
3.6 = 2.3 -0.05d+0.1d
1.3 = 0.05d
26 = d
sub d = 26 into n+d=46
n+26=46
n=20
Check by subbing n=20 and d=26 into 0.05n +0.1d
0.05(20) +0.1(26)
1+2.6 = 3.6

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