Johnson Electronics makes calculators. Consumer satisfaction is one of the top priorities of the company’s management. The company guarantees the refund of
money or a replacement for any calculator that malfunctions within two years from
the date of purchase. It is known from past data that despite all efforts, 12% of the
calculators manufactured by this company malfunction within a 2-year period. The
company recently mailed 550 such calculators to its customers.
a. Find the probability that exactly 32 of the 550 calculators will be returned for
refund or replacement within a 2-year period.
b. What is the probability that 30 or more of the 550 calculators will be returned for
refund or replacement within a 2-year period?
a. What is the probability that 15 to 35 of the 550 calculators will be returned for
refund or replacement within a 2-year period?