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3 years ago

How to find the sum of 2+4+6....+40?

Mathematics

1 answer:

grandymaker [24]3 years ago

3 0

Answer 420.
a, is the first term. d is difference.
Since this is an arithmetic progression, I use this formula.
Un = nth term
Sn = sum of terms.
First find the number of terms, which is 20.
Then use the second formula to find the sum.

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