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 !

Which equation represents the line that passes through the points and (4, 10) and (2, 7)? y = 3/2x - 11y = 3/2x +4y = - 3/2x + 19y = - 3/2x + 16

Graph the equation by plotting point x=2

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6