You can find the 15th term by using the formula \(a_n = a_1 *r^{n-1}\), where \(a_1\) is the first term of the sequence, r is the common ratio, and n is the number of the term you want to find.
\(a_n = a_1 *r^{n-1}\) Plug in your information (the common ration is x4) \(a_{15} = 3 * 4^{14}\) Simplify the exponent \(a_{15} = 3 * 268435456\) Multiply \(a_{15} = 805306368\)
The 15th term of the sequence is 805306368.
6. 200, 40, 8, 1.6, ... Using guess and check, I found that the pattern here is ÷5, ÷5, ÷5, .... That can also be written as ×\(\frac{1}{5}\), ×\(\frac{1}{5}\), ×\(\frac{1}{5}\), ... When you are multiplying the terms of a sequence, that is a geometric sequence.
