SOLUTION: i have a collection of 25 pennies and dimes. their total value is $1.24. how many of each coin are there

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Question 1002488: i have a collection of 25 pennies and dimes. their total value is $1.24. how many of each coin are there
Found 2 solutions by CubeyThePenguin, MathTherapy:
Answer by CubeyThePenguin(3113) (Show Source):
You can put this solution on YOUR website!
p = number of pennies
d = number of dimes

p + d = 25
p + 10d = 124

Multiply the first equation by 10. We are eliminating the variable d.

10p + 10d = 250
p + 10d = 124

Subtracting, we get 9p = 126, or p = 14.

There are 14 pennies and 11 dimes.

Answer by MathTherapy(10555) (Show Source):
You can put this solution on YOUR website!
i have a collection of 25 pennies and dimes. their total value is $1.24. how many of each coin are there

If you happen to form the equations the way the other person did: P + D = 25, ad P + 10D = 124, you ABSOLUTELY and UNEQUIVOCALLY DON'T need to change ANY of the 2 equations. Just SIMPLY subtract the 1st from the 2nd to get: 9D = 99, and subsequently, D, or number of dimes to be: = 11.
Then, subtract 11 for 25 to get the number of pennies. That's all!!
No need to do any UNNECESSARY and time-consuming changes to any if the 2 equations. It's JUST SENSELSS and STUPID to do so!