2.


3.

4.

This fraction is

5.

6.

7.

8.

9.
from 8.45am to 12.45pm - 4 hours

I earn

10.
48 minutes = 1 hour - 12 min
21.15 - 1 hour = 20.15
20.15 + 12 min =
20.27
11.

12.


I get up at 6.45am
13.

14.

15.
Answer:
$80, $48
Step-by-step explanation:
The original price was x.
The price is reduced by 40%. The markdown is 40% of x, or 0.4x.
The actual dollar amount of the markdown is $32.
That means that 0.4x must equal $32.
We set up an equation and solve for x, the original price.
0.4x = 32
Divide both sides by 0.4
x = 32/0.4
x = 80
The original price is $80.
The markdown is $32.
$80 - $32 = $48
The marked down price is $48.
Answer: $80, $48
Answer:
Step-by-step explanation:
Data given and notation
represent the sample mean
represent the sample standard deviation
sample size
represent the value that we want to test
represent the significance level for the hypothesis test.
t would represent the statistic (variable of interest)
represent the p value for the test (variable of interest)
State the null and alternative hypotheses.
We need to conduct a hypothesis in order to check if the true mean is different from 7.1 ppm, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:
(1)
t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".
Calculate the statistic
We can replace in formula (1) the info given like this: