Question

There are 5 consecutive odd numbers. If the difference between square of the 2 of first two odd number and the of the 2 last two odd numbers is 396, what is the smallest odd number?
A) 29
B) 27
C) 31
D) 33

Answer 1

b option is the right answer

Let the odd numbers be represented by : a, b, c, d, e

then b= a+2, b= a+4, c=a+6 d =a+8

[(a+6 + a+8)/2]^2 -[(a +a+2)/2]^2 = 492

[a+7]^2 - [a+1]^2 = 492

(a+7)(a+7) - (a+1)(a+1) = 492

(a^2 + 14a +49) - (a^2 + 2a +1) = 492

12a + 48 = 492

a = (492 - 48) 12

a = 37

Answer 2

There are 5 consecutive odd numbers. If the difference between square of the 2 of first two odd number and the of the 2 last two odd numbers is 396, what is the smallest odd number?

A) 29

B) 27

C) 31

D) 33

Consecutive Odd Numbers If x is any odd number, then x and x + 2 are consecutive odd numbers. E.g. 7 and 9 are consecutive odd numbers, as are 31 and 33.