SOLUTION: rachel has 20 nickels, dimes and quarters worth $3.70. if she has twice as many quarters as dimes, how many nickels does she have? i COMPLETELY forgot how to do this kind of pr

Algebra ->  Expressions-with-variables -> SOLUTION: rachel has 20 nickels, dimes and quarters worth $3.70. if she has twice as many quarters as dimes, how many nickels does she have? i COMPLETELY forgot how to do this kind of pr      Log On


   

Question 83360: rachel has 20 nickels, dimes and quarters worth $3.70. if she has twice as many quarters as dimes, how many nickels does she have?
i COMPLETELY forgot how to do this kind of problem. sorry!
Found 2 solutions by Kalmetam, checkley75:
Answer by Kalmetam(43) About Me  (Show Source):
You can put this solution on YOUR website!
Well Just try a simple chart, just see a number and itself x2 so you're left with the number of nickels. It has to add up to 20
N D Q Price:
17 1 2 1.45
14 2 4 1.90
11 3 6 2.35
8 4 8 2.80
5 5 10 3.20
2 6 12 3.70
It looks like there are 2 nickels!



Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
2d+d+n=20, n=20-3d
25*2d+10*d+5(20-3d)=370
50d+10d+100-15d=370
45d=370-100
45d=270
d=270/45
d=6 number of dimes.
2*6=12 number of quarters.
20-6-12=2 number of nickles.
proof
12*25+6*10+2*5=370
300+60+10=370
370=370