The sum of 6 consecutive odd numbers is 144. What will be the product of first number and the last number?
A513
B551
C609
D567
Answer:
B. 551
Read Explanation:
Let six consecutive odd numbers be x, x + 2, x + 4, x + 6, x + 8 and x + 10.
Now,
x + x + 2 + x + 4 + x + 6 + x + 8 + x + 10 = 144
⇒ 6x + 30 = 144
⇒ 6x = 144 – 30
⇒ x = 114/6
⇒ x = 19
∴ x + 10 = 29
Product of the first number and the last number = 19 × 29 = 551
