In the equation

, a is the initial amount and b is the growth factor. So our initial amount is 30 and our growth factor is 8.3. Your correct choice for this is A.
Answer:
10
Step-by-step explanation:
we can solve this using basic algebra
We set up the equation using the info that each video costs $5 and that we but 12 of them
12(1 * 5) + x = 70
(Please note: 1x = x)
12(5) + x = 70
60 + x = 70
60 - 60 + x = 70 - 60
x = 10
The least common multiple of 2 and 4 is 4 .
Here's a useful hint to keep in mind:
If the smaller number is a factor of the larger number,
then the larger number is the LCM of both of them.
PEMDAS
Parentheses, exponents, multiplication, division, addition, subtraction.