Answer:
74
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!! :))