The standard deviation of the mileage for the sample of convertibles is 1.98977 miles.
<h3>What is standard deviation? </h3>
Standard deviation is used to determine how the values in a group differs from the mean of the values in the group. It is a measure of variation.
<h3>What is the standard deviation of the mileage? </h3>
In order to determine the standard deviation, take the following steps:
- Determine the mean of the observation:
(25 + 25 + 24 + 21 + 21 + 21 + 20) / 7 =22.43
- Determine the difference between each value and the mean and then square the result:
(25 - 22.43)² = 6.6049
(25 - 22.43)² = 6.6049
(24 - 22.43)² = 2.4649
(21 - 22.43)² = 2.0449
(21 - 22.43)² = 2.0449
(21 - 22.43)² = 2.0449
(20 - 22.43)² = 5.9049
Sum of squared difference = 27.7143
- Determine the mean of the square differences and then find the square root of the mean:
√27.7143 / 7 = 1.98977
To learn more about standard deviation, please check: brainly.com/question/12402189
Let the unknown number be x.
<span>sum of a number and one: x + 1
</span>
<span>sum of a number and one is doubled: 2(x + 1)
</span>
<span>three less than the number: x - 3
2(x + 1) = x - 3
2x + 2 = x - 3
x + 2 = -3
x = -5
The number is -5.
</span>
Answer:
The sale price will be 143.20
Step-by-step explanation:
20% of 179 is 35.80
179 - 35.80 = 143.20