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What is the sum of the first 21 even numbers? FAST!!!
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4 votes
What is the sum of the first 21 even numbers? FAST!!!

User Tolokoban
by
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1 Answer

0 votes

Answer:

462

Explanation:

Sum = n/2 x (a + Tn)

= 21/2 x (2 + 42)

= (21 x 44)/ 2

= 924/2

2 + 4 + 6 + 8 + 10 + 12 + . . . . + 42 = 462

User Neil From Ohio
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4.1k points
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