<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>
The answers are 1/5,2/5,3/5,and 4/5
Step-by-step explanation:
Brother Answer is 12 inches
1 would be D.
2. Is A since 3^2=9 and -3^2=9 And 9-9=0. Im pretty sure A. For number 3. Just because the two x-values are 3 and -3. I’m sorry if I’m wrong on #3.
Cos(68)=z/24
Z=24cos(68)
Find the answer by the calculator
Second question,
Cos(x)=16/34
X=cos^-1(16/34)
Use calculator
