Question

10. Joe has a collection of nickels and dimes that is worth $2.10. If the number of dimes was tripled and the number of nickels was increased by 24, the value of the coins would be $5.70. How many nickels and dimes does he have?

Answer 1

5n+10d=210
5(n+24)+10(3d)=570 -->5n+120+30d=570 -->5n+30d=450
So set up a system:
5n +10d = 210
-5n - 30d =-450
-----------------
0n -20d=-240
d=12 -->5n+10(12)=210 --> 5n+120=210 -->5n=90 --> n=18
Final Answer: 12 dimes, 18 nickels.

Answer 2

Thank You so much !