Answer: True.
Step-by-step explanation: um hm.
Step-by-step explanation:
First calculate the z-score.
z = (x − μ) / σ
z = (11.07 − 11.5) / 2.7
z ≈ -0.16
From a z-score table:
P(z<-0.16) = 0.4364
The proportion of babies that weigh less than 11.07 lbs is 0.4364.
P = 10% = 0.1
q = 1 - 0.1 = 0.9
P(at least one defective calculator) = P(1) + P(2) + P(3) + P(4) = 1 - P(0)
The brobability of a binomial distribution is given by

where: n = 4

Therefore,
P(at least one defective calculator) = 1 - 0.6561 = 0.3439
Get a new one or ask someone to use theirs.