Answer:
15
Step-by-step explanation:
Brainliest please .
Thank you,
6/6+ 12*180
= 1+ 2,160
= 2,161
The final answer is 2,161~
A (it’s a slight increase)
if you have a TI-84 calculator you could solve this problem in seconds.
Using the <u>concepts and properties</u> of mean and standard deviation, it is found that:
- Each test score has to be multiplied by 4 and increased by 27.
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- The mean of a data-set is the <u>sum of all values in the data-set divided by the number of values</u>.
- If all values are increased by x, the <u>mean will also be increased by x.</u>
- If all values are multiplied by x, the <u>mean will also be multiplied by x</u>.
- The standard deviation of a data-set is the<u> square root of the sum of the differences squared of each value and the mean, divided by the number of values.</u>
- If all values are increased by x, the <u>standard deviation remains constant</u>.
- If all values are multiplied by x, the <u>standard deviation is also multiplied by x.</u>
In this problem:
- First, we multiply, to find the desired standard deviation, then we add, to find the desired mean.
- Standard deviation of 3 we want to be 12, thus, we multiply each test score by 4, as .
- Multiplying by 4, the standard deviation will already be 12, but the mean will be 48.
- We want a mean of 75, thus, we have to increase each test score by 27, as 75 - 48 = 27.
A similar problem is given at brainly.com/question/20640860