Home › AP Statistics › Statistics › Discrete Random Variables › A bakery puts an average of 12 loaves of bread o…
A bakery puts an average of 12 loaves of bread on its shelf every 30 minutes. What is the average number of loaves put on the shelf in a five-minute interval?
A12 loaves
B6 loaves
C0.4 loaves
D2 loaves
Answer & Solution
Correct answer: D. 2 loaves
1. The rate is 12 loaves per 30 minutes.
2. Scale that rate to a 5-minute window: (5/30)(12) = 2.
3. So the average number of loaves in five minutes is 2, which becomes the μ for a Poisson model of that interval.
4. Option B uses a 15-minute scaling by mistake, and option B forgets to rescale the interval at all.
_Source: OpenStax Introductory Statistics (CC BY 4.0), Ch 4 "Discrete Random Variables", section 4.6 Poisson Distribution_
Related questions
Mrs. Plum's cats wake her up an average of ten times per week, so X ~ P(10). What is P(x≤5The average number of children a Spanish woman has in her lifetime is 1.47, so X ~ P(1.47)Pierre, an amateur chef, drops an average of 1.5 pieces of egg shell into each cake he bakContinuing the IRS audit example with X ~ P(2), what is P(x≥3), the probability that at leThe chance of an IRS audit for a return over $25,000 is about 2% per year. For 100 such taA manufacturer finds 3% of its Christmas light bulbs defective. For a string of 100 lightsFor 200 days with a 1.02% chance of low seismic activity per day in Alaska, the binomial mText message users send or receive an average of 41.5 texts per day. Converted to an hourl