MATHEMATICS MIDDLE SCHOOL

Find the sum of the arithmetic sequence. 3, 5, 7, 9, ..., 21

Answers

Answer 1

Answer:

The answer is:

120

Given the arithmetic sequence

3, 5, 7, 9, ..., 21

The first term a = 3 & a common difference d = 5 - 3 = 7 - 5 = ... = 2

If there are n number of terms in the above A.P. then last term l = 21 will be the nth term given as:

l = a + (n - 1)d

21 = 3 +(n − 1)2

n = 10

Hence the sum of given arithmetic progression (A. P.) up to 10 terms is given general formula.

Sn = n/2(a + l)

S10 = 10/2(3 + 21)

= 120

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Answers

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Answers

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planck's constant: 6.63 times 10^-34
I just searched on bing!
Hope it helps!

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