Mathematics, 30.12.2019 23:31 natlovesfood
An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 40 hours. if a sample of 30 bulbs has an average life of 780 hours, how large a sample is needed if we wish to be 96% confident that our sample mean will be within 10 hours of the true mean?
Answers: 1
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
.
, so 
is the standard deviation of the population and n is the size of the sample.
Other questions on the subject: Mathematics
Mathematics, 21.06.2019 18:00, leianagaming
Describe the relationship between the angles of similar triangles and the sides of similar triangles
Answers: 1
Mathematics, 21.06.2019 18:40, helpme6191
(mc 02.03) what set of reflections and rotations would carry rectangle abcd onto itself? reflect over the y-axis, reflect over the x-axis, rotate 180° rotate 180°, reflect over the x-axis, reflect over the line y=x reflect over the x-axis, rotate 180°, reflect over the x-axis rotate 180, reflect over the y-axis, reflect over the line y=x
Answers: 1
Mathematics, 21.06.2019 19:50, nawafcanada
On a piece of paper graft y+2> -3x-3 then determine which answer matches the graph you drew
Answers: 2
You know the right answer?
An electrical firm manufactures light bulbs that have a length of life that is approximately normall...
Questions in other subjects:
