Step-by-step explanation:
relax ! don't panic. just breathe deeply and then focus again.
a geometric sequence means that every new term is created by multiplying the previous term by a constant factor.
this factor is given here as 3/2.
this is called common ratio, because of that building rule the ratio of 2 consecutive terms is
an/an-1 = factor = 3/2
the first term is 3.
so,
a1 = 3
a2 = a1×3/2 = 3×3/2 = 9/2
a3 = a2×3/2 = a1×3/2 × 3/2 = 3× 3/2 × 3/2 = 27/4
we see
an = an-1 × 3/2 = a1 × (3/2)^(n-1) = 3 × (3/2)^(n-1)
and therefore
a8 = 3 × (3/2)⁷ = 3× 2187/128 = 6561/128 = 51.2578125
