Tammy has scored 82, 78, and 93 on her previous three tests. What score does she need on her next test so that her average (mean
1 answer:
Answer:
She needs a grade of 71 on her next text.
Step-by-step explanation:
Mean of a data-set:
The mean of a data-set is the sum of all values in the data-set divided by the number of values.
Tammy has scored 82, 78, and 93 on her previous three tests.
Thus, her grades are 82, 78, 93 and x, in which x is her grade in the fourth test.
There are 4 tests.
What score does she need on her next test so that her average (mean) is 81?
We have to find x when the mean is 81. So
She needs a grade of 71 on her next text.
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Now, we gather all the terms with x in it on the left side, and the numbers without x on the right. We get:
And then we can make this
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