How many coins of each kind does she have

Question

Rita has a collection of 123 coins consisting of nickels, dimes, and quarters. The number of dimes is 7 more than one-third the number of nickels, and the number of quarters is twice the number of dimes. How many coins of each kind does she have?

Answer 1

d = 7 +( n/3)

 

q = 2d

 

n + d + q = 123

 

n + 7 + (n/3) + 2 x (7 + [n/3]) = 123

 

3n + 21 + n +42 + 2n = 369

 

6n = 306

 

n = 51

 

d = 24

 

q = 48