He would have 21 before he bought the 10 stamp because 31-10=21
It takes about 14.55 years for quadruple your money
<em><u>Solution:</u></em>
Given that,
At 10 percent interest, how long does it take to quadruple your money
Rule of 144:
The Rule of 144 will tell you how long it will take an investment to quadruple
Here,
Rate of interest = 10 %
Therefore, number of years to quadruple your money is obtained by dividing 144 by 10
<em><u>Rule of 144 Formula: </u></em>

Where:
N = Number of many years times.
144 = Is the constant variable.
R = Rate of interest.

Thus it takes about 14.4 years for quadruple your money.
<em><u>Another method:</u></em>
If initial amount is $ 1 and it if quadruples it should be $ 4
We have to find the number of years if rate of interest is 10 %
Let "n" be the number of years
Then we can say,



Thus Option D 14.55 years is correct
The volume of the rectangular prism can be express in standard polynomial as follows:
x³ + 12x² + 35x
<h3>How to find the volume of a rectangular prism?</h3>
volume of a rectangular prism = lwh
where
- l = length
- w = width
- h = height
Therefore,
let
height = x
width = x + 5
length = x + 5 + 2 = x + 7
Therefore,
volume = x(x + 5)(x + 7)
volume = x(x² + 7x + 5x + 35)
volume = x(x² + 12x + 35)
volume = x³ + 12x² + 35x
learn more on volume here: brainly.com/question/2005063
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Answer:
1 3/100
21-24squareroot7/100
21
=24squareroot7/100
Step-by-step explanation: