Scores on a test in a very large class are bell-shaped and symmetric. The mean on the test was 75, and the standard deviation was 5. What percent of the scores were above 75?
Answers
Answer:
50% of the scores were above 75
Step-by-step explanation:
Problems of normally distributed(bell-shaped) samples are solved using the z-score formula.
In a set with mean and standard deviation
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What percent of the scores were above 75?
This is 1 subtracted by the pvalue of Z when X = 75. So
has a pvalue of 0.5
1 - 0.5 = 0.5
50% of the scores were above 75
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Answers
Maybe the figures should be 53 and 20??
Let's let Billy = A
The formula to use for work problems is
Time = (A*B) / (A+B)
53 = ( (A +20)* A) / (A +20 + A) )
53 = ( A^2 + 20A ) / (2A + 20)
A^2 + 20A -106A -1060
A^2 -86A -1060
A = 96.935
Bobby Mows in 116.935 minutes
O False
Answers
Answer:
True
Step-by-step explanation:
The skip interval in systematic random sampling is computed by dividing the number of potential sampling units on the list by the desired sample size .
Systematic sampling is a type of probability sampling method in which sample members from a larger population are selected according to a random starting point but with a fixed, periodic interval (the sampling interval).
Sampling interval is calculated by dividing the population size by the desired sample size
Answers
78.5 = 3.14 * r^2
r^2 = 78.5 / 3.14 = 25
r = radius = 5 answer
Answers
Answer:
Hope you understand my writing!
Answers
3/4 of an hour is equal to 45 minutes.
To find 3/4 of an hour, we need to multiply the value of one hour by 3/4.
One hour is equal to 60 minutes.
To calculate 3/4 of an hour:
= 3/4 x 60 minutes
= (3/4) x 60
= 45 minutes.
Therefore, 3/4 of an hour is equal to 45 minutes.
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Answer:
45 minutes
Step-by-step explanation:
so 1 hr= 60 minutes so you do 3/4 x 60min which is 45 minutes. Feel Free to mark Brainliest and have a great day!
b t>w
C not possible to tell
Answers
sin(0) = 0
sin(90) = 1
This means the larger angle will give a larger sine value.
sin(w) > sin(t) -----> w > t
Final answer:
Given the values sin(t) = 0.45 and sin(w) = 0.89, both for angles in the first quadrant, we can determine that the angle w is greater than the angle t. This is because in the first quadrant, the sine of an angle increases as the angle increases.
Explanation:
The sine of an angle in the unit circle, sin(t) or sin(w), is the y-coordinate of the point where the angle intersects the unit circle. The angles are in quadrant 1, where sine values are positive, as are the angles themselves. Given sin(t) = 0.45 and sin(w) = 0.89, we know that the sine of an angle increases as the angle increases within the first quadrant (from 0 to 90 degrees). Therefore, sin(w) > sin(t) implies that w > t.
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