A handful of 65 coins consist of pennies, nickels and dimes. The number of nickels is 4 less than twice of pennies, and there are 13 more dimes than nickels. How many coins of each kind are there? Solve using Gauss-Jordan Elimination.

Answer 1

start writing the facts:

p+n+d = 65
n = 2p-4
d = n+13

For elimination, standardize the lines:

p+n+d = 65
-2p+n = -4
-n+d = 13

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