Let's see what the options look like when we multiply the expressions in brackets:
(first, i multiply both parts of the second bracked by the first part of the first bracket, and then the same with the second part of the first bracket:
<span>(1) (3x - 3)(x - 2))
3x2 +6x -3x +6// this is not correct
(2) (3x + 3)(x - 2) </span>
3x2-6x+3x-6//this is not correct
(3)
3(x + 1)(x - 2)
3(x2-2x+x-2)//simplifying:
3(x2-x-2)//multiplying:
3x2-3x-6)
- so this is not correct either
(4) 3(x - 1)(x - 2)
3(x2-2x - x + 2)
3(x2-3x +2)
3x2-9x +6 - well, here is our winner!
Answer:
An expression that would show how much the student paid is 3(4) + 0.95, which can be solved to be 12.95
Step-by-step explanation:
We know that we need to multiply the number of cans (3) by the price of the cans (4). We also know the sales tax for the total is 0.95, which can simply be added to the end.
C=2πr
r=C/(2π), now the surface area is:
A=4πr^2, using r found above we have:
A=4πC^2/(4π^2)
A=C^2/π, we are given that C=28 so:
A=28^2/π in^2
A=784/π in^2
A≈250 in^2 (to nearest square inch)
Answer:
![Interval = [666.78, 781.62]](https://tex.z-dn.net/?f=Interval%20%3D%20%5B666.78%2C%20781.62%5D)
Step-by-step explanation:
Given
The data for 25 undergraduates
Solving (a): Range and Standard deviation
The range is:
From the dataset:
So:
The standard deviation is:
First, calculate the mean
So, the standard deviation is:
Solving (b): The interval of the 95% of the observation.
Using the emperical rule, we have:
![Interval = [\bar x - 2*\sigma, \bar x+ 2*\sigma]](https://tex.z-dn.net/?f=Interval%20%3D%20%5B%5Cbar%20x%20-%202%2A%5Csigma%2C%20%5Cbar%20x%2B%202%2A%5Csigma%5D)
![Interval = [724.2 - 2*28.71, 724.2 + 2*28.71]](https://tex.z-dn.net/?f=Interval%20%3D%20%5B724.2%20-%202%2A28.71%2C%20724.2%20%2B%202%2A28.71%5D)
