4a+3b-(-2a-3b)
=4a+3b+2a+3b
=6a+6b
=6(a+b)
The mean distance for a group is the sum of individual numbers over the number of data. The mean distance of Group A is (1+1.5+3+3.2+2.8+1.5+1.8+2.5+2.2)/9=2.17 The mean distance of Group B is (<span>2+2.5+3.2+3+1.8+2.4+3+1.5+1.8)/9=2.36. Therefore, the mean is greater for group B than group A, but not doubling.</span>
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:
Answer:
the opposite of 10 is -10
Step-by-step explanation:
Graph it on -10
Answer:
x=3
Step-by-step explanation:
2(4-3x)+5(2x-3)=20-5x
8-6x + 10x - 15= 20-5x
subtract 8 from 15
subtract 6x from 10x getting you
4x-7= 20-5x
add 5x to both sides
add 7 to both sides
getting you
9x=27
divide by 9 to both side getting you x=3