Question

find the seventh term of the geometric sequence with a3=125 and r=5

Answer 1

geometric sequence
\[a_n = a + r^{n-1}\]
\[a_3 = 125\]
\[r = 5\]
\[125 = a + 5^{3-1}\]
find a
then
\[a_7 = a+r^{7-1}\]