Carolyn has $2.55 in her purse in nickels and dimes. The number of nickels is nine less than three times the number of dimes. Find the number of each type of coin.

Hi, the answer is;

Answer:

12 dimes and 27 nickels

Step-by-step explanation:

.05N +.1d = 2.55

N = 3d - 9

0.05 (3d-9) + 0.1d = 2.55

0.15d - 0.45 + 0.1d = 2.55

0.25d = 2.55 + 0.45

0.25d = 3

D = 12

N = 3 (12) - 9

N = 36 - 9

N = 27