14. Isaiah bought a total of 22 pieces of candy. The tootsie rolls cost 3 cents each and the jolly ranchers cost 5
cents each. If Isaiah spent a total of $90 cents, how many of each candy did he purchase?

Respuesta :

Answer:

  • 10 tootsie rolls, 12 jolly ranchers

Step-by-step explanation:

Let tootsie rolls be t, jolly ranchers be r.

The cost of them is 3t and 5r and we have following equations:

  • t + r = 22
  • 3t + 5r = 90

Solve the system by elimination, multiply the first equation by 3 and subtract from the second equation:

  • 3t + 5r - 3t - 3r = 90 - 66
  • 2r = 24
  • r = 12

Find the value of t:

  • t = 22 - 12 = 10

Let tootside rolls be x and jolly ranchers be y

  • x+y=22=>x=22-y
  • 3x+5y=90-(2)

Substitute in eq(2)

  • 66-3y+5y=90
  • 66+2y=90
  • 2y=24
  • y=12

And

  • x=22-12=10