Question

Find the sum of even integer from 2 to 2002

Answer 1

Answer:1003002

Step-by-step explanation:

Sum of even integers = n*(n+1) , where 'n' = number of numbers

Here, n = 1001

Sum = 1001 * 1002 = 1003002

Answer 2

Answer: 1003002

Step-by-step explanation:

Method 1

2+4+6+.......+2002

=2(1+2+3+....+1001)

=2x1001x1002/2 [because 1+2+...+n=n(n+1)/2]

=1003002

Given is an AP with a=d=2 and an=2002

a+(n-1)d=2002

2+(n-1)2=2002

2n=2002

n=1001

So Sum Sn=n/2(a1+an)

=1001/2(2+2002)

=(1001x2004)/2

1003002