Question

The sum of three consecutive odd numbers is 21. Find the numbers.

Answer 1

Let the first odd number be x.
Then, the next consecutive odd numbers will be (x + 2) and (x + 4).
According to the question:
x + (x + 2) + (x + 4) = 21
or, 3x + 6 = 21
or, 3x + 6 $-$ 6 = 21 $-$ 6 [Subtracting 6 from both the sides]
or, 3x = 15
or, $\frac{3x}{3}=\frac{15}{3}$ [Dividing both the sides by 3]
or, x = 5
∴ Required numbers are:
x = 5
x + 2 = 5 + 2 = 7
x + 4 = 5 + 4 = 9