Question

In an A.P. first term is 4 and the last term is 136. The sum of all terms is equal to 2380. Then n is equal to?​

Answer 1

Answer:

can u send the pic

Step-by-step explanation:

as it can't understand like that

Answer 2

$\huge\tt{\bold{\underline{\underline{Question᎓}}}}$

In an A.P. first term is 4 and the last term is 136. The sum of all terms is equal to 2380. Then n is equal to?

$\huge\tt{\bold{\underline{\underline{Answer᎓}}}}$

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Given :a = 4

l(last term)=136

The sum of all terms =2380

Formula used here :

$sn = \frac{n}{2} (a + l)$

$= > 2380 = \frac{n}{2} (4 + 136)$

$= > 2380 = \frac{n}{2} (140)$

$= > \frac{2380}{140} = \frac{n}{2}$

$= > 2380 \times 2 = 140n$

$= > 4760 = 140n$

$= > n = \frac{4760}{140} = \frac{476}{14} = 34$

Hence,value of n =34

$\mathcal{Other \:Realated\:formulas:- }$

$\bold{\boxed{sn = \frac{n}{2} [a + (n - 1)d]}}$

$\bold{\boxed{an = a + (n - 1)d}}$

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