u have a geometric sequence. To find the common ratio, divide the second term by the first term. 6/12 = 1/2
an = a1 r^(n-1)
n = term to find = 10
a1 = first term = 12
r = common ratio = 1/2
now we sub
a(10) = 12 1/2(10 - 1)
a(10) = 12 1/2^9
a(10) = 12 1/512
a(10) = 12/512 reduces to 3/128 ,<== ur 10th term
