Question

how many multiples of 4 lies between 10 and 250

Answer 1

Multiples of 4 between 10 and 250 --

12 , 16 ..... 148

Tn = a + ( n - 1 ) d

= 148 = 12 + ( n - 1 ) × 4

= 148 - 12 = ( n - 1 ) × 4

= 136 / 4 = n - 1

= 34 + 1 = n

n = 35 Ans

Answer 2

First multiple of 4 which lie between 10 and 250 is 12
The last multiple of 4 which lie between 10 and 250 is 248
Therefore ,AP is of the form 12, 16, 20.........248.
First term =a = 12
Common difference = d = 4
Last term =an= 248
Using formula
an= a+(n-1)d
248 = 12+(n-1)4
248 = 12+4n-4
248 = 8+4n
248-8 =4n
240 =4n
n = 240/4 = 60
So, we can say that there are 60 multiples of which lie between 10 and 250