Answer:
Step-by-step explanation:
The z-score tells us how many standard deviations a value is away from the mean.
The formula is:
where x is the value, is the mean, and s is the standard deviation.
We want to find the z-score for the score of an 83, the mean is 72, and the standard deviation is 5.
Substitute the values into the formula.
Solve the numerator.
Divide.
The z-score is 2.2, which means the score of 83 is 2.2 standard deviations above the mean.
The price of the discount is $25 x 0.15 = $3.75
The price of the book with discount is $25 - $3.75 = $21.25
Answer:
5 miles
Step-by-step explanation:
distance = speed · time
Tom's distance = (50 mi/h)·(2.5 h) = 125 mi
Albert's distance = (65 mi/h)·(2 h) = 130 mi
Albert drove 130 -125 = 5 miles farther than Tom.
Answer:
44.5 yards
Step-by-step explanation:
Start with the formula of the circumference of a circle.
C = πd
Now all you have to do is plug in the numbers.
279.46 = (3.14)d
Divide both sides by 3.14
d = 89
But since you're finding the radius, you have to divide the diameter by 2.
89/2 = 44.5