Question

please answer this question ​

Answer 1

${\huge{\boxed{\frak{\red{Qu}{\blue{es}{\orange{t}{\pink{io}{\green{n}}}}}}}}}$

★ In an A.P. , the first term is -4 , the last term is 29 and the sum of all its term is 150 . Find it's common difference.

✿ Solution -

In this A.P.,

-4,.......,29

Here ,

a(first term) = -4

l(last term) = 29

using formula for last term ,

l = a + (n-1)d

29 = -4 +(n-1)d

(n-1)d = 33 ______(i)

Now,

Given sum = 150

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

$150 = \frac{n}{2} ( - 4 + 29)$

$300 = n(25)$

$n = 12$

Now putting the value of n in equation (i)

(12-1)d =33

11d = 33

d = 3

${\huge{\boxed{d = 3}}}$

Answer 2

Step-by-step explanation:

first term a=4

last term = 29

sum of all term is 150

let D be the common different

ATQ