Let x be the score Amaya gets on the final test. She wants her average of all 3 tests to be between 80 and 89:
<span>80 ≤ (78 + 91 + x) / 3 ≤ 89 </span>
<span>Multiply everything by 3: </span>
<span>240 ≤ 78 + 91 + x ≤ 267 </span>
<span>240 ≤ 169 + x ≤ 267 </span>
<span>Subtract 169 from everything: </span>
<span>240 - 169 ≤ x ≤ 267 - 169 </span>
<span>71 ≤ x ≤ 98 </span>
<span>Answer: </span>
<span>She needs to score between 71 and 98 to get a B for the course.</span>
Answer:
0.8 OR
Step-by-step explanation:
The reciprocal of any number is the number that it multiplies by to equal 1.
The reciprocal can be found by simply converting the number into a fraction and then 'flipping' the fraction as any number multiplied by its reciprocal is 1.
E.g.
No. X/Y * Y/X (its reciprocal) = 1
So, to find the reciprocal of 1.25,we should first convert 1.25 to a fraction.
1.25 = 125/100
Now we just flip 5/4 to get our reciprocal:
= 0.8
Test: 0.8 * 1.25 = 1
The reciprocal of 1.25 () is 0.8 ().
Hope this helped!
The standard deviation of a point estimator is the <u>standard error.</u>
"The point estimate is used to estimate the exact value of any parameter. For example, an internet poll says that 45% of Americans are concerned for the environment."
"Point estimates is a good measure but the problem with this parameter is that the sample of the statistics may vary so that there is a chance of sampling error."
"As the researcher is unable to presume that closeness of the sample statistics parameter with respect to the parameter so researcher refers to calculate the standard error instead of point estimate."
To learn more about standard error here
brainly.com/question/13179711
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Answer: x=1
Step-by-step explanation:
You need to open up the parenthesis so you multiply every term inside the parenthesis by -7.
1. -7x + 14 + 1 = 15 -7x
2. Combine like terms -7x + 15 = 15-7x
The two sides of the equation are the same so that means that x=1
Answer:
The answer is <u><em>7</em></u>!
Step-by-step explanation:
(x-4) (x) = 21, x^2 - 4x = 21, x^2 - 4x - 21 = 0, (x - 7) (x + 3) = 0, x = 7 and -3; x can't be negative so the answer is 7!
x = 7 and x - 4 (other side) = 3