Use the geometric series formula to find the 9th term in this progression : 12 18 27...
Formula for nth term in a geometric progression = ar^n-1
workings:
a=12
r=1.5 because 18/12 = 1.5
Thus, using ar^n-1 --> 12 * 1.5^8 = 307.54... or 308 (to 3sf)
(In an ideal scenario question we'd be working with a whole number as the answer, but i created this question in about a minute so couldn't ensure the answer would be a whole number).
PF
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