Well,
The distance from the earth to the moon, FYI, is over 200,000 miles. That is a LONG distance. We are trying to find a reasonable unit of measurement.
What do we mean by "reasonable?" We mean that that unit should be able to express the distance as a number that is not huge or tiny. In other words, we want it to be as close as possible to 1.
mm, or millimeters, is a tiny unit. It is not reasonable.
cm, or centimeters, is also a tiny unit. It also is not reasonable.
m, or meters, is also a relatively small unit. It also is not reasonable.
km, or kilometers, is the largest of the four. In km, the distance from the earth to the moon is about 363,000 km. That's not too bad.
However, if these weren't the only options, I would choose Mm, or megameters, which would put the distance at 363 Mm.
The correct option is D.
The total number of dancers in the school is 150.
Answer:
The solution to the system of equations is:
x = 2, and y = -1
Explanation:
Given the pair of equations:
4x + 5y = 3 ..........................................................................(1)
2x + 3y = 1............................................................................(2)
To solve this by elimination:
Multiply equation (2) by 2, to eliminate x
Equation (2) becomes
4x + 6y = 2 .........................................................................(3)
Subtract equation (1) from (3)
4x - 4x + 6y - 5y = 2 - 3
y = -1 ....................................................................................(4)
Multiply equation (1) by 3 and equation (2) by 5 to eliminate y
Equation (1) becomes
12x + 15y = 9 .......................................................................(5)
Equation (2) becomes
10x + 15y = 5 ........................................................................(6)
Subtract equation (6) from (5)
12x - 10x + 15y - 15y = 9 - 5
2x = 4
Divide both sides by 2
x = 4/2 = 2 ............................................................................(7)
From equations (7) and (4)
x = 2, and y = -1
The predicted value of hardness at 37 hours is 243.87 and an 85% confidence interval for the mean hardness is (242.12, 245.61). At 41 hours, the predicted hardness is 252 and an 85% confidence interval for mean hardness is (249.83, 254.18). The confidence interval for X is equals to 41 which is wider because the value 41 is farther away from the sample mean X than is 37. As an outcome, the standard error for the prediction is larger.
You subtract 7% from 32=29.76
Then you subtract 8% from 29.76=27.379