Find all pairs of consecutive even positive integers both of which are larger than 8 such that their sum is less than 25.
Find all pairs of consecutive even positive integers both of which are larger than 8 such that their sum is less than 25.

Answer : Let the pair of consecutive even positive integers be x and x + 2. So, it is given that both the integers are greater than 8

Therefore,

x > 8 and x + 2 > 8

When,

x + 2 > 8

Subtracting 2 from both the sides in above equation x + 2 – 2 > 8 – 2

x > 6

Since x > 8 and x > 6 Therefore,

x > 8

It is also given that sum of both the integers is less than 25 Therefore,

x + (x + 2) < 25 x + x + 2 < 25 2x + 2 < 25

Subtracting 2 from both the sides in above equation 2x + 2 – 2 < 25 – 2

2x < 23

Dividing both the sides by 2 in above equation

x < 11.5

Since x > 8 and x < 11.5

So, the only possible value of x can be 10 Therefore, x + 2 = 10 + 2 = 12

Thus, the required possible pair is (10, 12).