Question -
Answer -
We know that all evenintegers will have a common difference of 2.
So, AP is 102, 104,106, тАж, 998
We know, a = 102, d =104 тАУ 102 = 2, an┬а= 998
By using the formula,
an┬а= a+ (n-1)d
998 = 102 + (n-1)2
998 = 102 + 2n тАУ 2
2n = 998 тАУ 102 + 2
2n = 898
n = 898/2
= 449
By using the formula,
Sum of n terms, S =n/2 [a + l]
= 449/2 [102 + 998]
= 449/2 [1100]
= 449 [550]
= 246950
тИ┤ The sum of all evenintegers between 101 and 999 is 246950.