Question

MEDAL
Find the missing term of the geometric sequence. 45, ____, 1620.
A) 9720
B) 51
C) 6
D) 270

Answer 1

GS is of the form a , ar, ar^2 ....

where a = first term and r = common ratio

Hint: divide the 3rd term by the first and you get r^2

Answer 2

so r^2 = 1620 / 45

- froom this you can find the value of r

then missing 2nd term = ar