Melody can cycle for 30 miles against the wind in the same amount of time that it takes to cycle 56 miles with the wind. If the speed of the wind is 3mph, what is Melody's speed when she cycles with the wind?



Answer with Solution:​

Respuesta :

Answer:

  • 12.92 mph

Step-by-step explanation:

Given:

  • Speed of the wind = 3 mph
  • Speed in calm weather = x
  • Speed with the wind = x + 3
  • Speed against the wind = x - 3

We know that:

  • distance = time*speed or
  • time = distance / speed

We have equal time in both cases so comparing d/s ratios:

  • 30/(x - 3) = 56/(x + 3)

Solve for x:

  • 56(x - 3) = 30(x + 3)
  • 56x - 168 = 30x + 90
  • 56x - 30x = 90 + 168
  • 26x = 258
  • x = 258/26
  • x ≈ 9.92

The speed with the wind is:

  • 9.92 + 3 = 12.92 mph