Question 741240
multiples of 3

3,6,9,.........
n=100
a=3
d=3
sn=n/2[2a+(n-1)d)]

=>100/2[6+99*3]
=>50*303
=> 15150

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even integers
a=2
d=2
n=100
Sn=n/2[2a+(n-1)d]

=50[4+99*2]

=50(202)

=10100

Find the difference