It's a rational number. 9 is a perfect square. What you have asked is written as -sqrt(9), which can be written as -sqrt(3*3) which is - 3. That's perfectly OK. What would not be OK is something like -sqrt(10) which is irrational because it cannot be represented as a fraction or a whole number or a repeating decimal or a decimal that terminates.
a. What percent of people earn less than $40000?
Solution: Let S be the random variable of a salary of employee (in $), S ~ N(50000,20000). Then the random
variable X =−50000
20000
~N(0,1).
( < 40000) = ( <
40000 − 50000
20000 ) = ( < −0.5) = (−0.5) = 0.3085375.
Here Φ(x) denotes the cumulative distribution function of a standard normal distribution.
Answer: 31%.
b. What percent of people earn between $45000 and $65000?
Solution:
(45000 < < 65000) = (
45000 − 50000
20000 < <
65000 − 50000
20000 ) = (−0.25 < < 0.75)
= (0.75) − (−0.25) = 0.7733726 − 0.4012937 = 0.3720789.
Answer: 37%.
c. What percent of people earn more than $70000?
Solution:
( > 70000) = ( >
70000 − 50000
20000 ) = ( > 1) = 0.8413447.
Answer: 84%.
Answer: 26 years old
Step-by-step explanation:
Since Scott is four more than double the age of Todd, start by taking away four from Scott's age.
56-4=52
Then take half of that because that would be double of Todd's age
52/2=26
Todd is 26 years old.
The original perimeter is 32ft.
The dimensions of the new rectangle are 72 ft wide and 24 ft long.
The new perimeter is 192 ft.
When the dimensions are multiplied by 6, the perimeter also multiplied by 6.
Total = Principal * (1 + rate)^years
Total = 3,300 * (1.018)^5
Total = 3,300 *
<span>
<span>
<span>
1.0932988468
</span>
</span>
</span>
Total =
<span>
<span>
<span>
3,607.8</span></span></span>9
