The 4th and 7th term of a GP are 16 and 2 respectively.

Question

Find.
(a) the 1st term.
(b) the common ratio.
(c) the sum of the first 3 terms.

Answer 1

r^3 = 2/16 = 1/8
so r = 1/3
a = 16/r^3 = 16*27 = ____
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