Answer:
Option A is true
The researchers proved that exercise causes weight loss only for high school students.
Step-by-step explanation:
We are told that the researchers found a high correlation, 0.93, between amount of exercise and weight lost.
Now, looking at each of the options;
- A is True because due to the high correlation, the research proves that exercise causes weight loss but only for high school students.
- B is not true because we are told the correlation is very high at 0.93. Thus, it is untrue that there is no proven causation.
-C is not true because there's no where that the researchers have completely proved that exercise causes weight loss generally. It is only peculiar to the high school students studied.
-D is not true because the 93% is just a correlation and not a percentage of those who lost weight
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Assumptions
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Let x be the amount of 25% orange juice
Let y be the amount of 10% orange juice
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There are 15 litres of 13% orange juice
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x + y = 15
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The 15 litres of juice is 13% orange juice
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0.25x + 0.1y = 15 x 0.13
0.25x + 0.1y = 1.95
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Rewrite the equations and solve for x and y
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x + y = 15 ----------------------- (Equation 1)
0.25x + 0.1y = 1.95 ----------- (Equation 2)
(Equation 1):
x + y = 15
x = 15 - y ----------- (Substitute into Equation 2)
0.25 (15 - y) + 0.1y = 1.95
3.75 - 0.25y + 0.1y = 1.95
0.15y = 1.8
y = 18 ÷ 0.15
y = 12 ------------- (substitute into Equation 1)
x + y = 15
x + 12 = 15
x = 15 - 12
x = 3
x = 3 and y = 12
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Answer: 3 liters of 25% of orange juice with 12 liters of 10% orange juice
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Answer:
17
Step-by-step explanation:
Answer:
13
Step-by-step explanation:
-2x - 4 > 10
Multiply both sides by -1 and reverse the inequality symbol.
2x + 4 < -10
Now subtract both sides by 4.
2x + 4 - 4 < -10 - 4
2x < -14
Divide both sides by 2.
2x/2 < -14/2
x < -7
