Question

the first term of an A.P. is-3 and tenth is 24 find 20th term

Answer 1

$\textbf {Hey there, here is the solution.}$

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First term = a1 = -3 (Given)

Tenth term = a10 = 24 (Given)

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Find the difference, d, in the AP:

Given that in an AP series:

an = a1 + (n - 1)d

24 = -3 + (10 - 1)d

24 = -3 + 9d

9d = 27

d = 3

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Find the AP series:

an = a1 + (n - 1)d

an = -3 + (n - 1) 3

an = -3 + 3n - 3

an = 3n - 6

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Find the 20th term:

a20 = 3(20) - 6

a20 = 54

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Answer: The 20th term is 54

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⭐$\textbf {Cheers }$⭐