Question

the 12th term from yhe end in AP 13,18,23,.....,158​

Answer 1

Answer :-

103

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Given :-

• An AP as 13, 18, 23,........158

To Find :-

• 12th term from the end

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Solution :-

We have,

First term, a = 13

Common difference, d = 18 - 13 = 5

Last term, l = 158

n = 12

∴ 12th term from the end = {l - (n - 1)d}

Tn => { 158 - (12 - 1)5}

Tn => 158 - 55

Tn => 103

Hence, the value of 12th term from the end is 103.

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Answer 2

Answer :

${\red\bigstar\Large\bold{\underline{\textsf{\orange{Given:}}}}}$

• A.P. = 13, 18, 23, ... , 158

${\red\bigstar\Large\bold{\underline{\textsf{\orange{To\:Find:}}}}}$

• $\sf {12}^{th}\:term\:from\:last$

${\red\bigstar\Large\bold{\underline{\textsf{\orange{Sølution:}}}}}$

▶ FORMULA USED :

$\bold{\boxed{\sf{\pink{{n}^{th}\:term\:from\:last\:=\:l\:-\:(n\:-\:1)d}}}}$

Here , l = 158 , n = 12 , d = 18 - 13 = 5

➡ 158 - ( 12 - 1)5

➡ 158 - (11)5

➡ 158 - 55

➡ 103

${\orange\bigstar\large\bold{\underline{\sf{\red{{12}^{th}\:term\:from\:last\:=\:103}}}}}$

✴ NOTE :

If we have to find $\sf{n}^{th}$ term from start then -

▶ Formula used —>

${\sf{\purple{ a_n\:=\:a\:+\:(n\:-\:1)d}}}$

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