SOLUTION: A company manufacturing light bulbs claims that an average light bulb lasts 300
days. A potential customer randomly selects 15 bulbs for testing. The sampled bulbs
last an averag
Algebra.Com
Question 927115: A company manufacturing light bulbs claims that an average light bulb lasts 300
days. A potential customer randomly selects 15 bulbs for testing. The sampled bulbs
last an average of 290 days, with a standard deviation of 50 days. If the company’s
claim were true, what is the probability that 15 randomly selected bulbs would have
an average life of no more than 290 days?
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!
mean = 300
P(x ≤ 290) = P( z < -10/(50/sqrt(15)) =P(z < -.7746)
Using a TI calculator 0r similarly a Casio fx-115 ES plus
P(x ≤ 290) =P(z < -.7746) = normalcdf(-100, -.7746)= .2193 0r 21.93%
RELATED QUESTIONS
A company manufacturing light bulbs claims that an average light bulb lasts 300
days. A... (answered by ewatrrr)
Please help me.
t distribution related problem.
Acme corporation manufactures light... (answered by Positive_EV)
A light bulb manufacturer claims his light bulbs will last 500 hours on the average. The... (answered by stanbon)
A light bulb company claims that the 40 watt light bulb it sells has an average life of... (answered by Theo)
A manufacturer of halogen light bulbs claims that the lives of the light bulbs are... (answered by stanbon)
1. Liwanag Bulb Company claims that it sells light bulbs with an average life of
1000... (answered by Theo)
A light bulb manufacturer randomly checks light bulbs. Of 1,000 light bulbs, 30 light... (answered by stanbon,drk)
a manufacturer of light bulbs claims that its new light bulb has a mean life of 1000... (answered by stanbon)
a manufacturer of light bulbs claims that its new light bulb has a mean life of 1,000... (answered by Fombitz)