Factorize the following 3x + 12

if this was a equation you would first subtract 12 from the other number then divide it by 3

3(x+4)

Step-by-step explanation:

Check 3(x+4), when you use the distributive property, you get 3x + 12, so this is correct. (sorry, I'm really bad at explaining...)

We conclude that the car have mileage rating less than 30 miles per gallon.

Step-by-step explanation:

We are given the following in the question:  

Population mean, μ = 30 miles/gallon

Sample:

26, 24, 20, 25, 27, 25, 28, 30, 26, 33

where are data points, is the mean and n is the number of observations.  

Sum of squares of differences = 110.4

Sample size, n = 10

Alpha, α = 0.05

First, we design the null and the alternate hypothesis

We use one-tailed t test to perform this hypothesis.

Formula:

Putting all the values, we have

Now,

Since,                  

We fail to accept the null hypothesis and reject it.

We conclude that the car have mileage rating less than 30 miles per gallon.

b) We assumed that the level of significance is 0.05 that is 5%.