Respuesta :

Answer:

  • 12.5

Step-by-step explanation:

This is a proportional relationship:

  • y = kx

Use a pair of values to find the coefficient of proportionality (5, 2.5):

  • 2.5 = 5k
  • k = 2.5/5 = 0.5

k = 0.5 units represents a cost of a text message.

25 text messages cost:

  • 25*0.5 = 12.5 units