<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:
y = -2x -3
Step-by-step explanation:
- the altitude trough F is a perpendicular line to the line DE
- find slope of line DE
D ( x2 = -5, y2 = -1); E (x1 = 3, y1 = 3)
slope m = (y2-y1) / (x2-x1) = (-1-3) / (-5-3) = -4/ -8 = 1/2
-find equation of the altitude trough F
lines that are perpendicular have the slope negative reciprocal (negative reciprocal of 1/2 is -2)
y= -2x +b , for point F(1, -5)
-5 = -2*1 +b, add 2 to both sides
-5 +2 = b, combine like terms
-3 =b
equation of the altitude trough F is y = -2x -3
Answer:
the awnser would be 2
Step-by-step explantion
u have 1 apple and get 1 from a friend and that adds up to 2
