The number of responses to a survey are shown in the Pareto chart. The survey as
ID: 3074179 • Letter: T
Question
The number of responses to a survey are shown in the Pareto chart. The survey asked 1029 adults how they would grade the quality of their public schools. Each person gave one response. Find each probability. (a) Randomly selecting a person from the sample who did not give the public schools an A (b) Randomly selecting a person from the sample who gave the public schools a grade better than aD (c) Randomly selecting a person from the sample who gave the public schools a D or an F (d) Randomly selecting a person from the sample who gave the public schools an A or B 002625Q 133 63 ResponseExplanation / Answer
Solution:-
a) The probability of selecting a person from the sample who did not give the public schools an A is 0.9388.
Number of person from the sample who did not give the public schools an A = 1029 - 63 = 966
Total number of persons = 1029
The probability of selecting a person from the sample who did not give the public schools an A = 966/1029 = 0.9388
b) The probability of selecting a person from the sample who gave the public schools a grade better than a D is 0.6171.
Number of person from the sample who gave the public schools a grade better than a D = 313 + 259 + 63 = 635
Total number of persons = 1029
The probability of selecting a person from the sample who gave the public schools a grade better than a D = 635/1029 = 0.6171
c) The probability of selecting a person from the sample who gave the public schools a D or an F is 0.3829.
Number of person from the sample who gave the public schools a D or an F = 261 + 133 = 394
Total number of persons = 1029
The probability of selecting a person from the sample who gave the public schools a D or an F = 394 / 1029 = 0.3829
d) The probability of selecting a person from the sample who gave the public schools an A or B is 0.3149.
Number of person from the sample who gave the public schools an A or B = 261 + 63 = 324
Total number of persons = 1029
The probability of selecting a person from the sample who gave the public schools an A or B = 324/1029 = 0.3149