g A small survey of iPad owners found 15% have an iPad Classic and 85% have an iPad Pro. Further, it was found that 77% of the iPad Classic owners purchased an AppleCare extended warranty while 68% of the iPad Pro owners purchased an AppleCare extended warranty.

required probability is 0.8335

Explanation:

Lets say we have a sample size of 1000

15% have ipad classic = 15% of 1000 = 150

85% have ipad pro = 85% of 1000 = 850

77% of ipad classic owners purchased apple care extended warranty = 77% of 150 = 115.5

68% of ipad pro owners purchased apple care warranty = 0.68*850 = 578

Probability = favorable/total

Total = purchased apple care warranty = 115.5 + 578 = 693.5

Favorable = ipad pro = 578

Required probability is 578 / (693.5) = 0.8335