Question 1001562
d = number of dimes
n = number of nickels
p = number of pennies
The problem says there are two more nickels than dimes and three times as many pennies as dimes:
d+2(0.05)= n
3d= p
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0.10d+0.05*n+0.001p= 0.64
Substitute by plugging into this equation the equivalent values above:
0.10*d + 0.05*d+2(0.05) + 0.01*3d= 0.64
Now solve for d:
0.10*d + 0.05*d+2(0.05) + 0.01*3d= 0.64
0.18d+0.10=0.64
0.18d= 0.54
d= 3 There are 3 dimes, and the problem says
n= d+2= 5 nickels and
p= 3d= 3*3= 9 pennies
3(0.10)+ 5(0.05)+9(0.01)= 0.64
0.30+0.25= 0.09= 0.64
0.64= 0.64 We have the correct answer