I need help with a systems of equations problem.

Question

Bill wanted to buy a slush at the store, so he checked his piggy bank. He only has dimes and nickels in it, and he had a total of 35 coins. He also has 5 more nickels than dimes. Which of the following slush sizes is the largest slush he could buy with his money? a) $2.99 b)$1.89 c) 2.49 d) 2.79

Answer 1

n=# of nickels

d=# of dimes

n=d+5 (5 more nickels than dimes)

n+d=35

substitute (n=d+5)

d+5+d=35

2d+5=35

2d=35-5

2d=30

d=30/2

d=15 dimes

n=15+5

n=20 nickels

15 dimes=$1.50

20 nickels=$1.00

total amount of money is $2.50

c) $2.49 is the answer