Answer:
Due to the higher z-score, he did better on the SAT.
Step-by-step explanation:
When the distribution is normal, we use 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.
Determine which test the student did better on.
He did better on whichever test he had the higher z-score.
SAT:
Scored 1070, so 
SAT scores have a mean of 950 and a standard deviation of 155. This means that
.



ACT:
Scored 25, so 
ACT scores have a mean of 22 and a standard deviation of 4. This means that 



Due to the higher z-score, he did better on the SAT.
Answer:
(-3.07, 11.07)
Step-by-step explanation:
Given that a sports writer wished to see if a football filled with helium travels farther, on average, than a football filled with air. To test this, the writer used eighteen adult male volunteers. These volunteers were randomly divided into two groups of nine subjects each.
Group Group One Group Two
Mean 300.00 296.00
SD 8.00 6.00
SEM 2.67 2.00
N 9 9
The mean of Group One minus Group Two equals 4.00
standard error of difference = 3.333
df = 16
t = 1.2000
Margin of error = 3.3333* t critical = 3.3333*2.121
95% confidence interval of this difference: From -3.07 to 11.07
Answer:
1. L= A/W
2. 4m
Step-by-step explanation:
We can define this problem as a word problem relating to mensuration of flat shapes, a
rectangle
1. Let the length be L and the width be W
Given
Area A= 6m²
W= 1.5m
We know that the area of a rectangular shape is
Area = L x W
The expression for the length is
L= A/W
2. The solution for the length is
6=1.5L
L= 6/1.5= 4m
In general, √(y²) = |y|, since y can be positive or negative and y² would have the same value either way.
So,
1) if y > 0, then |y| = y, and
-15√(y²) = -15 |y| = -15y
2) if y < 0, then |y| = -y, and
-√(16y²) = -|4y| = -|4| |y| = -4 (-y) = 4y
Answer:
5641 55/81
Step-by-step explanation:
you can simplify the equation by removing the parenthesis.
this means that you also have to solve the ^4 part.
this would be
5641 55/81
I know that this is a large number but that is what happens when you do ^4.