Question

Find the sum of all natural number between 300 and 600 which are divisble by 7​

Answer 1

Answer:

..........................................................

Answer 2

Answer:

19264

Step-by-step explanation:

the numbers divisible by 7 between 300 and 600 are

301+308+315+...+595

7(43+44+45+...+85)

here the AP is 43+44+45+..+85

where a=43 and d=1

last=a+(n-1)d

85=43+(n-1)1

n=85-42=43

s=n/2(first+last)

s=43/2(43+85)

s=2752

s=2752×7=19264