Suppose that the lifetimes of a certain kind of light bulb are normally distributed with a standard deviation of 120 hours. If exactly 95% of the bulbs die before 920 hours, find the mean lifetime of the bulbs. Carry your intermediate computations to at least four decimal places. Round your answer to at least one decimal Place

f(x) is going down by 4

step-by-step explanation:

(its either that or its going left by 4)

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

answer: two angles are called supplementary if they add up to 180°. example: the two angles (140° and 40°) are supplementary because they add up to 180°.

step-by-step explanation: