Question

find the sum of all natural number between 150 to 200 which is divided by 7​

Answer 1

Answer:

1225

Step-by-step explanation:

In between 150 and 200, 154 is the first number and 196 is the last number which is divisible by 7.

This forms an AP of:

a = first term = 154

d = common difference = 7

l = last term = 196

Using nth term = a + (n - 1)d: let there be n terms

=> 196 = 154 + (n - 1)7

=> 42 = (n - 1)7

=> 6 = n - 1

=> 7 = n

Using S = (n/2) (a + l) :

=> sum of all terms = (7/2) (154 + 196)

=> sum of all terms = 1225

Answer 2

Answer:

$1225$

Step-by-step explanation:

In between 150 and 200, 154 is the first number and 196 is the last number which is divisible by 7

This forms an A P of :

A = first term = 154

B = common difference = 7

L = last term = 196

Using nth term = a + ( n - 1) d: let there be n terms

$⟹196 = 154 + (n - 1)7$

$⟹42 = (n - 1)7$

$⟹6 = n - 1$

$⟹7 = n$

Using s = ( n / 2) ( a + 1)

➩ sum of all terms = ( 7 / 2) ( 154 + 196)

➩sum of all terms = 1225