Question

What are the three consecutive numbers that we should start with to get 100 on the top ?

Answer 1

Let three consecutive number in the bottom row be x, x + 1 and x + 2.

Adding adjacent cells in the bottom row, we get

x + (x+1) = 2x + 1 …………………..(1)

Similarly,

(x + 1) + (x + 2) = 2x + 3 ……………………(2)

Adding (1) and (2) for the top most cell, we get

(2x+1) + (2x +3) = 4x + 4

Now we know that 4x + 4 = 100.

$\Rightarrow$ 4x = 100 - 4

$\Rightarrow$ 4x = 96

$\Rightarrow$ x = 96 ÷ 4 = 24

$\Rightarrow$ x + 1 = 24 + 1 = 25

$\Rightarrow$ x + 2 = 24 + 2 = 26

Thus, the three consecutive numbers are 24, 25 and 26.