They will both next happen in 2040
Joe completes an average of (10 ft)/(5 h) = 2 ft/hour. Bill completes an average of (10 ft)/(4 h) = 2.5 ft/hour. Together, they complete 2+2.5 = 4.5 ft/hour. At that rate, it will take them
... (120 ft)/(4.5 ft/h) = 26 2/3 h
Answer: The probability that 3 or more of the next 5 customers will order chocolate is 30%. 3/10
Sandy conducted her own experiment to answer this question. She observed what groups of 5 customers ordered. In her experiment, 30% of the time at least 3 of the customers ordered chocolate.
The fraction 30% is 3/10.