"<span>How much did your classmates typically spend on music downloads last year?" is a statistical question, and the units would </span>be both the number of students and how many downloads each individual bought.
The answer is the second option you are correct !
Answer:
The student took 2.5 minutes to paint 1 square foot.
Step-by-step explanation:
In order to know how long the student took to paint each square foot we first need to know the total area of the bulletin board. Since it is a rectangle we can compute it's area by multiplying the width and the height. That is:
area = 2*3 = 6 square foot
Since the student took 15 minutes to paint the whole board the pace at which he was working can be calculated by dividing the total area of the board by the time he took to paint all of it. So we have:
pace = 6/15 = 0.4 foot/min
To find how long it took him to paint 1 square foot we can divide it by the pace he was painting. We have:
time = 1/0.4 = 2.5 minutes
The student took 2.5 minutes to paint 1 square foot.
Answer:
Kendall's shirt cost 18.20
Step-by-step explanation:
12.75+8.50=21.25
39.45-21.25=18.20
Answer:
Step-by-step explanation:
Since the length of time taken on the SAT for a group of students is normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - u)/s
Where
x = length of time
u = mean time
s = standard deviation
From the information given,
u = 2.5 hours
s = 0.25 hours
We want to find the probability that the sample mean is between two hours and three hours.. It is expressed as
P(2 lesser than or equal to x lesser than or equal to 3)
For x = 2,
z = (2 - 2.5)/0.25 = - 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.02275
For x = 3,
z = (3 - 2.5)/0.25 = 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.97725
P(2 lesser than or equal to x lesser than or equal to 3)
= 0.97725 - 0.02275 = 0.9545