Question

The fourth term from the last of the AP -11, -8, -5 ...49 is

Answer 1

EXPLANATION

• GIVEN

series of ap = -11, -8, -5,..... 49

TO FIND FOURTH TERM FROM LAST

New ap series be = 49,46,43,40......

First term = a = 49

common difference = d = b - a

46 - 49 = -3

fourth term of ap = T4

T4 = a + 3d

49 + 3(-3)

49 - 9 = 40

Therefore,

Fourth term of ap = 40

Answer 2

QUESTION:

The fourth term from the last of the AP -11, -8, -5 ...49 is

☆SOLUTION:

We used the formula here;

$last \: term = l - (n - 1)d$

where;

l = last term

d = common difference

now come to main question ;

Here;

l = 49

d = -8-(-11)

d = -8+11

d = 3

Using the formula;

$l(4) = 49 - (4 - 1)3 \\ l(4) = 49 - 3 \times 3 \\ l(4) = 49 - 9 \\ l(4) = 40$

FINAL ANSWER :

$4th \: term \: frm \: last \: is \: 40$

Additional information:

Some other formula related to AP are;

$nth \: term = a + (n - 1)d$

where;

a = first term

d = common difference

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