Question 643043
Sean collects nickels and dimes. Every time he places a nickel into his collection, he places two dimes.
d = 2n
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After a week, he notices that the number of dimes, increased by twice the number of nickels, gives the same number of coins as three times the number of nickels, increased by 10.
d + 2n = 3n + 10
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How many coins does he have by the end of the week?
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Substitute for "d" and solve for n:
2n + 2n = 3n + 10
n = 10 (# of nickels)
Solve for "d":
d = 2n = 20 (# of dimes)
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Total number of coins: 10 + 20 = 30
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Cheers,
Stan H.