Answer:
2.28% of tests has scores over 90.
Step-by-step explanation:
Problems of normally distributed 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 proportion of tests has scores over 90?
This proportion is 1 subtracted by the pvalue of Z when X = 90. So
has a pvalue of 0.9772.
So 1-0.9772 = 0.0228 = 2.28% of tests has scores over 90.
Let us assume the number of children attending the movie = x
Let us also assume the number of adults attending the movie = y
Cost of admission for a children in the movie = $8
Cost of admission of an adult in the movie = $12
Number of people going to the movie on a certain day = 3200
Total amount collected from the movie theater = $33040
Then
x + y = 3200
And
8x + 12y = 33040
2x + 3y = 8260
Let us first take the equation
x + y = 3200
x = 3200 - y
Now we will put the value of x in the equation
2x + 3y = 8260
2(3200 - y) + 3y = 8260
6400 - 2y + 3y = 8260
y = 8260 - 6400
= 1860
Now we will put the value of y from the above deduction in the equation
x + y = 3200
x + 1860 = 3200
x = 3200 - 1860
= 1340
So the number of children going to the movie theater is 1340 and the number of adults going to the movie theater is 1860.
Answer:
24
Step-by-step explanation:
5(2) + 2(4 + 3)
5 x 2 + 2 x 7
10 + 14 = 24
Here you go! :D
Answer:
The solutions are given below:
Step-by-step explanation:
x(x-3)+4(x²+2)
= x²-3x+4x²+8
= x²+4x²+8-3x
= 5x²+8-3x
2(a+5)-3(a+7)
= 2a+10-3a-21
= 2a-3a+10-21
= -a-11
xy(x²yz-xy²z+xyz²)
= x³y²z-x²y³z+x²y²z²
-4(a²-2a+8)
= -4a²+8a-32
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Hope it helps !</h3>
