Answer:
(a) 2%
Step-by-step explanation:
A score of 60 is 2 standard deviations below the mean (80 -2·10 = 60). The empirical rule tells you that 95% of the distribution is within 2 standard deviations of the mean. The remaining 5% is split evenly between those that are more than 2 SD above the mean and those that are more than 2 SD below the mean.
That tells you the percentage who failed is about 2.5%. The best answer choice is 2%.
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<em>Additional comment</em>
The empirical rule is a little bit sloppy, but it gets you in the ballpark. The actual percentage is closer to 2.275%.
This question is incomplete
Complete Question
Tyler went to the supermarket to buy food for a food pantry. He has $36, and can carry up to 20 pounds of food in his backpack. Pasta costs $1 for a 1-pound package. Pasta sauce costs $3 for a 1.5 pound jar. Let x = the number of packages of pasta and y = the number of jars of pasta sauce. One package of pasta is the right amount to go with one jar of pasta sauce. What is the best numbers of packages of pasta and jars of pasta sauce to buy for the food pantry? Explain your reasoning.
Answer:
Eight is the best numbers of packages of pasta and jars of pasta sauce to buy for the food pantry.
Step-by-step explanation:
Let
x = the number of packages of pasta
y = the number of jars of pasta sauce.
He has $36, and can carry up to 20 pounds of food in his backpack. Pasta costs $1 for a 1-pound package. Pasta sauce costs $3 for a 1.5 pound jar.
x + 1.5y ≤ 20....... Equation 1
x = 20 - 1.5y
x × $1 + y × $3 = $36
x + 3y ≤ 36..... Equation 2
20 - 1.5y + 3y = 36
-1.5y + 3y = 36 - 20
1.5y = 16
y = 16/1.5
y = 8
And x = 8
Therefore,
Eight is the best numbers of packages of pasta and jars of pasta sauce to buy for the food pantry.
Answer:
The two expressions are not equivalent
Step-by-step explanation:
2(3x-6) = 6x-12 which is not equal to 6x+12 because of the positive and
negative signs
Answer:
9-x
Step-by-step explanation:
The difference between x and 3 is x-3.
Now 6 minus x-3:
6-(x-3)=
= 6-x+3
= 9-x
