Joe has a collection of nickels and dimes that is worth $8.55. If the number of dimes was tripled and the number of nickels was decreased by 2, the value of the coins would be $23.45. How many nickels and dimes does he have?

Question

amistre64 · Answer

.05n + .10d = 8.55

.05(n-2) + .10(3d) = 23.45

amistre64 · Answer

5n + 10d = 855
5(n-2) + 10(3d) = 2345

5n + 10d = 855
5n -10 + 30d = 2345


5n + 10d = 855
5n + 30d = 2355

d = (2345(5)-855(5))/(150-50) = 74.5  hmmm

amistre64 · Answer

oh , i typoed in a 2355 lol

amistre64 · Answer

75 dimes

amistre64 · Answer

8.55
-7.50
-----
  1.05 = 21 nickels right?