Answer:
D.27
Step-by-step explanation:
this is the answer i got hope it helped
Answer:
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Step-by-step explanation:
we know that
The mean score is the total of all scores divided by the total number of tests.
Let
x_1 ----> the score in the first math test
x_2 ----> the score in the second math test
x_3 ----> the score in the third math test
x_4 ----> the score in the fourth math test
we have
After taking the first 3 tests, his mean test score is 88 points
so

----> equation A
How many points does he need on his last test to raise his mean test score to 90 points?
so

----> equation B
substitute equation A in equation B

solve for x_4


Therefore
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Answer: x = 9.611 ; or ; x = 9 11/18 .
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Explanation:
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All angles of any triangle must add up to 180 degrees.
So, (10x - 4) + (8x + 3) + 91 = 180 ; Solve for "x" ;
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10x - 4 + 8x + 3 + 81 = 180 ;
Combine the "like terms" on the left-hand side of the equation:
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+10x + 8x = 18x ;
- 4 + 3 + 8 = 7 ;
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18x + 7 = 180 ;
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Subtract "7" from each side of the equation:
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18x + 7 - 7 = 180 - 7 ;
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to get:
18x = 173 ;
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Divide EACH side of the equation by "18" ; to isolate "x" on one side of the equation; and to solve for "x" ;
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18x / 18 = 173 / 18 ;
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x = 9.6111111111111111....
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Write as: 9.611 ; or; 9 11/18.
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Answer: K = -14
Step-by-step explanation: solve for k by simplifying both sides of the equation then isolating the variable