SOLUTION: I have a problem that I can't figure out.
Joe has a collection of nickels and dimes that is worth $7.40. If the number of dimes were doubled and the number of nickels were incr
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Joe has a collection of nickels and dimes that is worth $7.40. If the number of dimes were doubled and the number of nickels were incr
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Question 34165: I have a problem that I can't figure out.
Joe has a collection of nickels and dimes that is worth $7.40. If the number of dimes were doubled and the number of nickels were increased by 20, the value of the coins would be $13.20. How many dimes does he have?
I have been trying to work this but can't seem to get it set up right.
Thank you. Answer by Paul(988) (Show Source):
You can put this solution on YOUR website! Let the number of nickels be x
Let the number of dimes be y
Equation (1):
10y+5x=740
x=148-2y (subsitution)
2(10y)+5(x+20)=1320
20y+5x+100=1320
20y+5(148-2y)+100=1320
20y+740-10y+100=1320
10y=480
y=48
x=148-2(48)
y=52
Hence, there are 48 nickels and 52 dimes.
Paul.
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