first aircraft seats : x
second aircraft seats : y
third aircraft seats : z
The first aircraft has 73 more seats than the second aircraft: x = y + 73
The third aircraft has 57 fewer seats than the second aircraft: z = y - 57
Their total number of seats is 427: x + y + z = 427
solve these three equations, you will get:
x = 210 seats
y = 137 seats
z = 80 seats
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you can check your answer by:
x - y = 210 - 137 = 73 correct
and
z + 57 = 80 + 57 = 137 = y correct
