Quantity A: A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn at random. The probability that neither of the balls drawn is blue Quantity B: Tickets numbered from 1 to 20 are mixed up and then a ticket is drawn at random. The probability that the ticket drawn contains a number which is a multiple of 3 or 5

For Quantity A, the non-blue balls total 5, so the probability of picking two non-blue balls is 5C2 divided by 7C2, equaling 10/21. For Quantity B, the multiples of 3 or 5 up to 20 are 9 numbers, making the probability 9/20. Comparing 10/21 to 9/20 cross-multiplied gives 200 versus 189, meaning Quantity A is larger. The result is 1.

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