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2 votes
What is the probability that a number chosen at random from the 2, 4,5

and 6 times tables (up to the 12th multiple) is either a multiple of 3, prime or a
square number?

User Paul Sabou
by
3.2k points

1 Answer

7 votes

Answer:

Explanation:

2 4 5 6

4 8 10 12

6 12 15 18

8 16 20 24

10 20 25 30

12 24 30 36

14 28 35 42

16 32 40 48

18 36 45 54

20 40 50 60

22 44 55 66

24 48 60 72

I have set this table up in a spreadsheet and colored in the squares as they appear in the table above. I have not counted any number as a member of 2 categories twice. An example would be 36 which is a multiple of 3 and a perfect square.

I have answered the question as though the question took on the properties of a dart board: you through a dart and whatever you hit is counted either as prime, a multiple of 3 or a perfect square

That said, there are

primes: 2

multiples of 3: 24

Perfect squares: 4

Total number of choices: 12*4 = 48

Probability: 30 / 48 = 5/8 or 0.625

If you are supposed to use some other method of counting, please leave a note.

User Lemarr
by
3.2k points