7.
10% = 6
25% = 15
50% = 30
20% = 12
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8.
a = 35
b = 105
c = 140
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9.
15 is 30% of 50.
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10.
The punch recipe contains 25% lemonade:
24/6 = x/100
x=1/4 x 100 = 25%
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11.
520
multiply 650 by 80 amd then divide by 100
or simply multiply 650 by 0.8
to get 520 students.
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12.
Number of items checked = 300
Defective items = 3%
Number of defective items =
Number of defective items =
Number of defective items = 9
Number of items worked = Total items - Number of defective items
Number of items worked = 300 - 9 = 291
291 items of checked items worked.
Do 200/14 and get 14.2857142857 so about 14 boxes
Answer: $85,000
Step-by-step explanation:
Given : In a given population of two-earner male-female couples, male earnings have a mean of $40,000 per year and a standard deviation of $12,000.

Female earnings have a mean of $45,000 per year and a standard deviation of $18,000.

If C denote the combined earnings for a randomly selected couple.
Then, the mean of C will be :-

Hence, the mean of C = $85,000
<span>Multiply equation(2) with 4 so that coefficient of become same in both the equations(You can make coefficient of y same and can follow the following procedure.)
</span><span>* Subtract (3) from (1)
* </span>Divide both sides by -19
*Subtract 21 from both sides.
*Divide both sides by 4
so the solution is x= 3 and y= -7
Hope I helped you :)