Answer:
Step-by-step explanation:
![-2\dfrac{1}{3}-1\dfrac{1}{3}=-2\dfrac{1}{3}+\left(-1\dfrac{1}{3}\right)=-\left(2\dfrac{1}{3}+1\dfrac{1}{3}\right)\\\\=-\bigg[(2+1)+\left(\dfrac{1}{3}+\dfrac{1}{3}\right)\bigg]=-\left(3+\dfrac{1+1}{3}\right)\\\\=-3\dfrac{2}{3}](https://tex.z-dn.net/?f=-2%5Cdfrac%7B1%7D%7B3%7D-1%5Cdfrac%7B1%7D%7B3%7D%3D-2%5Cdfrac%7B1%7D%7B3%7D%2B%5Cleft%28-1%5Cdfrac%7B1%7D%7B3%7D%5Cright%29%3D-%5Cleft%282%5Cdfrac%7B1%7D%7B3%7D%2B1%5Cdfrac%7B1%7D%7B3%7D%5Cright%29%5C%5C%5C%5C%3D-%5Cbigg%5B%282%2B1%29%2B%5Cleft%28%5Cdfrac%7B1%7D%7B3%7D%2B%5Cdfrac%7B1%7D%7B3%7D%5Cright%29%5Cbigg%5D%3D-%5Cleft%283%2B%5Cdfrac%7B1%2B1%7D%7B3%7D%5Cright%29%5C%5C%5C%5C%3D-3%5Cdfrac%7B2%7D%7B3%7D)
Answer:
See below in bold,.
Step-by-step explanation:
There are 30-17 = 13 boys in the class.
a. Prob(First is a boy ) = 13/30 and Prob( second is a boy = 12/29).
As these 2 events are independent:
Prob( 2 boys being picked) = 13/30 * 12/29 = 26/145 or 0.179 to the nearest thousandth.
b. By a similar method to a:
Prob ( 2 girls being picked) = 17/30 * 16/29 = 136/435 = 0.313 to the nearest thousandth.
c. Prob (First student is a boy and second is a girl) = 13/30 * 17/29 = 221/870.
Prob ( first student is a girl and second is a boy) = 17/30 * 13/29 = 221/870
These 2 events are not independent so they are added:
Prob( one of the students is a boy) = 2 (221/870 = 221/435 = 0.508 to the nearest thousandth.
The formula for volume always involves three dimensions.
In this case, the volume of a cube is 
, where 
is the side length of the cube.
To solve for that side length, you'd need to use a cube root.
<span>204
First, lookup a standard normal table and see what the z-score is for 0.025 (one half of 100% - 95%) to allow for equal sized tails. You should find that the z-score is 1.96. That means that 95% of the time, the value should be within 1.96 standard deviations of the mean. Now let's calculate the standard deviation.
800 is 800 - 1200 = -400 to the left of the mean of 1200.
1600 is 1600 - 1200 = 400 to the right of the mean of 1200.
So we are an equal distance of 400 on both sides of the mean. And we know from the z-score of 1.96, that we're 1.96 standard deviations from the mean. So a little division will give us the standard deviation. Which is:
400 / 1.96 = 204.0816327
So the standard deviation of the light bulbs is 204</span>
Answer: it’s A
Step-by-step explanation:
