Concept explainers
Refer to Exercise 2.50. Hours after the rigging of the Pennsylvania state lottery was announced, Connecticut state lottery officials were stunned to learn that their winning number for the day was 666 (Los Angeles Times, September 21, 1980).
- a All evidence indicates that the Connecticut selection of 666 was due to pure chance. What is the
probability that a 666 would be drawn in Connecticut, given that a 666 had been selected in the April 24, 1980, Pennsylvania lottery? - b What is the probability of drawing a 666 in the April 24, 1980, Pennsylvania lottery (remember, this drawing was rigged) and a 666 in the September 19, 1980, Connecticut lottery?
2.50 Probability played a role in the rigging of the April 24, 1980, Pennsylvania state lottery (Los Angeles Times, September 8, 1980). To determine each digit of the three-digit winning number, each of the numbers 0, 1, 2, … , 9 is placed on a Ping-Pong ball, the ten balls are blown into a compartment, and the number selected for the digit is the one on the ball that floats to the top of the machine. To alter the odds, the conspirators injected a liquid into all balls used in the game except those numbered 4 and 6, making it almost certain that the lighter balls would be selected and determine the digits in the winning number. Then they bought lottery tickets bearing the potential winning numbers. How many potential winning numbers were there (666 was the eventual winner)?
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Mathematical Statistics with Applications
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