Fan and Medal
Sam has 15 coins, all nickels and dimes, with a total value of $0.90. How many of each coin does he have? (Let d = the number of dimes and n = the number of nickels).

A. Write a system of equations to model the problem. (5 points)

B. Solve the system. (5 points)

C. State your answer with the proper label or labels. (5 points)

Question

Fan and Medal
Sam has 15 coins, all nickels and dimes, with a total value of $0.90. How many of each coin does he have? (Let d = the number of dimes and n = the number of nickels).

A.  Write a system of equations to model the problem.  (5 points)

B.  Solve the system.  (5 points)

C.  State your answer with the proper label or labels.  (5 points)

anonymous · Answer

I figured it out, and he has 12 Nickels, and 3 Dimes.

anonymous · Answer

d + n = 15 so n = 15- d 

0.1 d + .05 n = 0.90 
0.1 d + .05 (15-d) = .90 
0.1d + .75 - .05 d = .90 
0.1 d - .5 d = .15 
.05 d = .15 
d = 3 

d+ n = 15 
3 + n = 15 
n = 12

anonymous · Answer

A. (d*x)+(n*y)=.90

mathmale · Answer

@greenlegodude57:  Thank you for your input.  Next time, however, please help Brian find the answer(s) HIMSELF; do NOT give away the answers or more than a fraction of the steps along the way.  Brian would benefit much more from learning to solve this problem himself than from having the answer dropped into his lap.

mathmale · Answer

Brian:  would you mind reading through GG's solution and then trying to solve the problem yourself, without help?  You'll need these skills later!