Answer:
Step-by-step explanation:
a+b I think
Answer: " x = 9 " .
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Explanation:
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To calculate the mean:
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The mean =
{the sum of all the values in the number set} ÷
{the number of values in the data set} ;
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To solve for "x" ;
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Given that the "mean" is: "8" ;
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8 = { 3 + 7 + 9 + 12 + x } / 5 ;
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↔ { 3 + 7 + 9 + 12 + x } / 5 = 8 ;
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→ { 3 + 7 + 9 + 12 + x } = 8 * 5 ;
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→ { 31 + x } = 40 ;
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↔ x + 31 = 40 ;
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Subtract "31" from EACH SIDE of the equation; to isolate "x" on one side of the equation; and to solve for "x" ;
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→ x + 31 − 31 = 40 − 31 ;
→ x = 9 .
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2x + 3x - 10 = 70
5x - 10 = 70
5x = 70 - 10
5x = 60
x = 60/5
x = 12
Now that we know the value of x,
the value of QSR = 3(12) - 10.
QSR = 36 - 10
QSR = 16
ANSWER: 16
It should be 2.5
Yeahhhhhh