How many multiples of 4 lie between 10 and 250?

Solution:

The first multiple of 4 that is greater than 10 is 12.

The next multiple will be 16.

Therefore, the series formed as;

12, 16, 20, 24, …

This an AP with the first term as 12 and a common difference as 4.

When we divide 250 by 4, the remainder will be 2. Therefore, 250 − 2 = 248 is divisible by 4.

The series is as follows, now;

12, 16, 20, 24, …, 248

Let 248 be the nth term of this AP.

First term, a = 12

Common difference, d = 4

an = 248

As we know,

an = a + (n − 1)d

248 = 12 + (n – 1) × 4

236/4 = n – 1

59 = n – 1

n = 60

Therefore, there are 60 multiples of 4 between 10 and 250.