Question

How many integers lie between 300 and 1000
which are exactly divided by 13 but not
divisible by 14 ?​

Answer 1

Step-by-step explanation:

Given  

How many integers lie between 300 and 1000 which are exactly divided by 13 but not divisible by 14 ?

So we have 312, 325,338----------988

So a = 312, d = 13 and an = 988

We know that

An = a + (n – 1)d

988 = 312 + (n – 1)13

988 = 312 + 13n – 13

So 299 + 13n = 988

13 n = 689

So n = 53  

Answer 2

Answer:

312,325,.........988

a=312,d=13,tn=988

tn=a+d(n-1)

988=312+(n-1)13

52=n-1

n=53