Question

find the 12th term of each arithmetic sequence

a4= 88 & a8=29

Answer 1

a12 = 29 + (88-29)

Answer 2

whaat?

Answer 3

@ankit042

Answer 4

a(12) = a(0) + (12-1)d
where you have to first find value of a(0) and d

Answer 5

use a(4)= a(0) +(4-1)d
and a(8) = a(0) +(8-1)d

Answer 6

... you just lost me ;0 i dont understand this at all...

Answer 7

from a4 to a5, a certain quantity X is added to a4.
from a5 to a6, a certain quantity X is added to a5.
etc.
so that
a4 + X + X + X + X = a8

to compute a12, you must add X, X, X, and X. (4X)
It turns out that if you look at a8-a4, it is already equal to 4X, so you don't have to know X personally, just 4X.

Answer 8

(* to compute a12, add 4X to a8)

Answer 9

what is 12?

a4 = 88
a8 = 29.

Therefore, 4X = 29 - 88 = -59,

and a12 = a8 + 4X = 29 + (-59).

Answer 10

ok.

( arithmetic sequence: from one number to another one, the SAME quantity is added each time. that's what is noted 'X' in my answers, and 'd' in @ankit042 's one.
To compute a12, we look at the difference between a8 and a4 so get an idea of what that quantity 'X' is. re-read the explanations.
(btw the ans. is -30)

Answer 11

Thanks :/

Answer 12

(look at this simpler example..
a4 = 5, a5 = 6.
find a6.
you see that from a4 to a5, the number 1 is added. this is the 'X' (or 'd').
a6 is simply a5 + 1.
your question is similar, but with other numbers.)

Answer 13

ohhh i think i get it nooow. do you think you could help with another?

Answer 14

ok type your question

Answer 15

a new question you mean :)

Answer 16

a20= 1.4 & a30 = 7.2

Answer 17

what do you have to compute? which a... ?

Answer 18

the 12th term , saame as before.

Answer 19

ok. the first thing is to find the 'X' between two consecutive numbers.

Between a20=... and a30=... , the difference is not 'X' but 10'X' because a30 is 10 steps further in the sequence. ok?

Answer 20

ohkay (:

Answer 21

so what is X ?

do you have to add or remove a few X's from a20 to find a12 ?

Answer 22

add ?

Answer 23

x from a 20 to find

Answer 24

oh yeaah , ohkay ...

Answer 25

find X, and then you find a12 = a20 - 8X = 1.4 - 8 X = ...

Answer 26

I explained above how to find X.
———
Between a20=... and a30=... , the difference is not 'X' but 10'X' because a30 is 10 steps further in the sequence.
———

a30 - a20 = 10X

Answer 27

-8.6 ?

Answer 28

a30 = 7.2, a20 = 1.4
a30-a20 = 7.2 - 1.4 = is not -8.6

Answer 29

did u find it out

Answer 30

ohkay nevermind i dont get it , i give up ;0 im tired of math.

Answer 31

call it a break :-|

Answer 32

alright..