Question

Find the 21st term of each arithmetic sequence

-1.45 , -2.9 , -4.35 , -5.8 , -7.25

Answer 1

do you see any pattern in this sequence ?

Answer 2

what is the common difference

Answer 3

nope , i have like 5 of these and i did 3 of them and i cant do the rest , including this one , i dont get this one.

Answer 4

know what common difference is ??

Answer 5

common difference(d) is the difference between consecutive term
d= 2nd term - 1st term = 3rd term - 2nd term = ....and so on

Answer 6

here, d = -2.9- (-1.45) = ...

Answer 7

= -1.45 ?

Answer 8

yes, correct
d = -1.45
now just use the general formula ,
\(\Large a_n = a_1 +(n-1)d\)

a1 = 1st term = -1.45
n = 21
d= -1.45

Answer 9

oh i got it , thanks.!!!!

Answer 10

welcome ^_^