Question

how many three digit numbers are divisible by 3 find thier sum​

Answer 1

Answer:

Step-by-step explanation:

102,105,108,............................999.

From above AP,

we have,

a= 102

d= 3

an= 999

n=?

Sn= ?

By Formula ;- an= a+ (n-1) d

999= 102 + (n-1) 3

999-102= (n-1)3

897= (n-1)3

897/3 = n-1

299+1= n

n= 300

By Formula ;- Sn= n/2 (a+l)

Sn= 300/2 (102+999)

150*1101

Sn= 165,150

Hope it will help u:)