The table shows some information about the lifetimes, t, in hours, of some lightbulbs.
Lifetime
Frequency
25 51
50 47
100 34
150 47
200 0
250 50
300 43
Estimate the mean lifetime of a bulb.
Give your answer rounded to 2 DP.

PLZZ HELP !

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e. g. 98.76543).

The two cylinders are similar. if the ratio of their surface areas is 9/1.44 find the volume of each cylinder. round your answer to the nearest hundredth. a. small cylinder: 152.00 m3 large cylinder: 950.02 m3 b. small cylinder: 972.14 m3 large cylinder: 12,924.24 m3 c. small cylinder: 851.22 m3 large cylinder: 13,300.25 m3 d. small cylinder: 682.95 m3 large cylinder: 13,539.68 m3

Find the zeros of each function. f(x) = x^2 + 5x - 6