SOLUTION: johnny got $1.12 in pennies and nickels from his mom. He got twice as many pennies as nickels. How many pennies and nickels did johnny get?

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Question 700501: johnny got $1.12 in pennies and nickels from his mom. He got twice as many pennies as nickels. How many pennies and nickels did johnny get?
Answer by Stitch(470) About Me  (Show Source):
You can put this solution on YOUR website!
Let P = number of pennies
Let N = number of nickels
Equation 1: 0.01P+%2B+0.05N+=+1.12
Equation 2: 2N+=+P
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Substitute 2N into equation 1 for P.
Equation 1: 0.01P+%2B+0.05N+=+1.12
0.01%2A%282N%29+%2B+0.05N+=+1.12
Simplify
0.02N+%2B+0.05N+=+1.12
Combine like terms
0.07N+=+1.12
Divide both sides by 0.07
highlight%28N+=+16%29
Now plug 16 into equation 2 for N
Equation 2: 2N+=+P
2%2A%2816%29+=+P
highlight_green%2832+=+P%29
Johnny has 32 pennies and 16 nickels.