A vacuum cleaner company has three machines, each making electric cords.
Machine 1 is the oldest and of all units it produces 1.2% do not meet quality standard (of not being damaged after an
abrupt change of voltage). Machine 2 produces 0.8% of bad units, while the newest, machine 3, makes 0.5% of units
with unacceptable quality. Of all the cords produced, 20% are made on machine 1, 35% are made on machine 2 and
the rest on the machine 3.
The cord is used as a part of vacuum cleaner that the company makes.
If a customer randomly buys a vacuum cleaner produced by this company, what is the probability that the cord does
not meet the quality standard?
SHOW WORK
P(bad cord) = P(bad cord from machine 1) + P(bad cord from machine 2) + P(bad cord from machine 3)
P(bad cord from machine 1) = 0.012 * 0.2 = 0.0024
P(bad cord from machine 2) = 0.008 * 0.35 = 0.0028
P(bad cord from machine 3) = 0.005 * 0.45 = 0.00225
P(bad cord) = 0.0024 + 0.0028 + 0.00225 = 0.007325
Therefore, the probability that the cord does not meet the quality standard is 0.007325.
impatient much?
Once is enough, thank you.
Repeated postings will not get faster or better responses.