How many multiples of 4 lie between 10 and 250?

Solution:

The multiples of 4 between 10 and 250 are 12, 16, 20, 24...., 248.

Let these numbers be n.

$a=12, d=4$

$\mathrm{t}_{\mathrm{n}}=248$

$\Rightarrow a+(n-1) d=248$

$\Rightarrow 12+(n-1) \times 4=248$

$\Rightarrow 4 n+8=248 \Rightarrow n=60$