Answers: 80 pennies and 160 nickels
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Step-by-step explanation:
We have n = 2p, which means we can replace every copy of n with 2p like so
0.01p + 0.05n = 8.80
100*(0.01p + 0.05n) = 100*8.80
p + 5n = 880
p + 5(2p) = 880
p + 10p = 880
11p = 880
p = 880/11
p = 80
There are 80 pennies
This leads to n = 2p = 2*80 = 160 nickels
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Check:
80 pennies = 80 cents
160 nickels = 5*160 = 800 cents
80 pennies + 160 nickels = 80 cents + 800 cents = 880 cents = $8.80
The answers are confirmed.