Respuesta :

Answer:

74

Step-by-step explanation:

55 + 80 + 75 + 76 = 286

Now, to find the average we divide by four.

286 ÷ 4 = 71.5

We know it can't be higher than 75 or 76 because his average would have increased more than just .5 points. So, it would be 74.

55 + 80 + 75 + 76 + 74 = 360

Divide by 5.

360 ÷ 5 = 72

Done!! :))