Answer:
First building = 456
Second building = 438
Third building = 383
Explanation:
First building = 73 + x
Second building = 55 + x
Third building = x
Total height of three buildings = 1277
(73 + x) + (55 + x) + (x) = 1277
73 + x + 55 + x + x = 1277
128 + x + x + x = 1277
128 + 3x = 1277
3x = 1149
x = 383
This is the height of the third building.
First building = 73 + x = 73 + 383 = 456
Second building = 55 + x = 55 + 383 = 438