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Probabilites question, should be easy..

The winner of each edition of WHATS THE SCORE? has the opportunity to scoop the jackpot in the winning score game. To be successful, all 5 questions must be answered correctly. The questions all have different numerical answers that add up to 20 altogether.

James is todays winner, and his winning score questions have been revealed as follows.

How many legs does a lacewing have?

How many days of the week begin with the same letter of the alphabet in Both French and German?

How many oscars did Marilyn Monroe win?

How many points are awarded for a field goal in American football?

How many stars are there on the flag of Tuvalu?

James knows that a lacewing is an insect, and therefore has 6 legs, that Mariyln Monroe did not win any Oscars, and that 3 points are awarded for a field goal in American football. However he has no idea at all of either of the other 2 answers, so he will have to guess.

Assuming that James doesn't make a silly mistake such as giving 5 answers that dont add up to 20, what chance does he have of winning the jackpot?

a) 1 chance in 3
b) 1 chance in 4
c) 1 chance in 5
d) 1 chance in 6


The correct answer is 1 chance in 4, but i dont understand how. I worked it out as one chance in 6 by listing the 6 possible combinations (cant use same number answer more than once, reducing the options)

possible combinations must add to 11 (20 - 6 legs - 0 oscars - 3 points)

so:

1 and 10
2 and 9
4 and 7
7 and 4
9 and 2
10 and 1

so i get one in 6 not one in 4??
(edited 7 years ago)
Original post by 2cool

How many days of the week begin with the same letter of the alphabet in Both French and German?


You need to think a bit further. What's the maximum value this - quoted question - can be? Hence....
Reply 2
Original post by ghostwalker
You need to think a bit further. What's the maximum value this - quoted question - can be? Hence....


Ohhh! can't be more than 7, so that rules out more options I see now...

Would not have expected that extra depth to the question, I'm glad I asked on here wouldn't have spotted that in a month of Sundays ! (which begs the question, are there 4 or 30 sundays in a month of Sundays? :P )

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