Question

sarah has dimes and nickels which total $1.65. the number of nickels she has is 3 less than the number of dimes. how many of each does she have?

Answer 1

let d=#dimes
10d=value dimes
d-3=#nickels
5(d-3)=value nickels

10d+5(d-3)= 165 total value=$1.65
10d+5d-15=165 distribute
15d-15=165 combine like terms
15d=180 add 15 to both sides
d=12 divide both sides by 15

You have 12 dimes and (d-3)nickels
or (12-3) nickels which is 9 nickels

Therefore, solution = 12 dimes and
9 nickels

Check: 12x.10=1.20
9x.05=0.45
Sum =1.65