Question

The sum of three consecutive multiples of 9 is 378. find the three multiples

Answer 1

let the first number be x.
second number= x +9
third number = x+9+9 = x+18
a/q  x + x+ 9 + x+18 = 378
      ⇒ 3x + 27 = 378
      ⇒ 3x = 378 -27
     ⇒  x = 351/3
      ∴  x = 117
so first number = 117
second number = 117+9 = 126
third number = 117+18 = 135
117 + 126+ 135 = 378
so 117, 126 and 135 are the 3 consecutive multiples of 9 whose sum is 378. 

Answer 2

solution :-

Given:-
The sum of three consecutive multiples of 9 is 378.

Let the first number be x.

second number= x +9

Third number = x+9+9 = x+18

Now

x + x+ 9 + x+18 = 378
=>3x + 27 = 378
=>3x = 378 -27
=>x = 351/3
=>x = 117

first number = 117

second number = 117+9 = 126

third number = 117+18 = 135

so 117, 126 and 135 are the 3 consecutive multiples of 9 whose sum is 378. 

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