Answer:

Step-by-step explanation:

20 can be written as a product of 4 and 5.

4 is a perfect square.

Square root of 4 is 2.

So an exponential equation is gonna be used for this problem. The formula for such is

, in which the a variable is the initial value and the b variable is the growth/decay rate.
For this situation, 1200 is gonna be your a variable since you've started out with it. And as for your b variable, its gonna be 107.3%, or 1.073, since it's increasing.
Your equation should look like this:

and from here just plug in 10 into the x variable and solve.
Multiply (1.073)^10 (don't round answers until the end), and take that answer and multiply it with 1200, your answer should be $2427.61.
Answer: 13.29%
Step-by-step explanation:
The formula to calculate the compound amount (compounded continuously) is given by :-
, where P is the principal amount , r is the rate of interest ( in decimal) and t is the time period.
Given : P= $ 35,000 , A= $257,000 and t=15 years
To find : r , we substitute all the values in the above formula , we get

Taking natural log on both the sides , we get

Hence, the annual interest rate = 13.29%
Answer: See explanation
Step-by-step explanation:
You didn't give the options but let me help out.
First and foremost, we should note that the value of the digit 2 in the number 135,284 is 200. Therefore, the value that is ten times as great as the value of the digit 2 in the number 135,284 would be:
= 10 × 200
= 2000
Therefore, the 2 must be in the thousands place. This can be seen in numbers such as:
172748.
Let’s make an equation
Let’s say x = amount of years after
Smith = 8, mother = 42
3(8 + x) = 42 + x
24 + 3x = 42 + x
2x = 18, x = 9
Solution: after 9 years