How to answer these questions ?

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1 Answer
Feb 24, 2018

#x = 15# for an AP

#x=9# for a GP

Explanation:

a) For an AP, the difference between consecutive terms is equal we just need to find the average of the terms on either side,

#(3+27)/2 = 15#

b) Since both #3# (#3^1#) and #27# (#3^3#) are powers of #3#, we can say that they form a geometric progression with a base of #3# and a common ratio of #1#.

Therefore the missing term is simply #3^2#, which is #9#.