Question

If you get the answers right you will get brainliest and get a thanks :-)

Answer 1

5.   3, 12, 48, 192, 768, ...

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.