# Probability question

Banned
Found 15th Nov 2009
anyone good at maths? This is annoying i know the answer should be simple but i cant work it out!

Q1- 10 people buy a raffle ticket for a chance of winning a cake. Each have an equal chancing of winning the cake. What is the probability of 1 person winning the cake?

Q2 - This time around 10 people buy a raffle ticket but this time there are two cakes to win. What is the probability of 1 person winning a cake?

The first question is easy the second one im not sure about.

any ideas?

Groups
1. Misc

is this a wind up?

2 in 10 or
1 in 5

Q1. 1 in 10 chance of winning

Q2. 1 in 5 chance of winning

1. 100 percent chance of one of them winning the cake, its a raffle.

2. 0% chance of one person winning a cake, either two people will win a cake or one person win two cakes.

harlzter;6900557

100 percent chance of one of them winning the cake, its a raffle.

Haha

Oh i love HUKD's lol

smallian;6900545

2 in 10 or1 in 5

you sure about that? surely after the first cake in question 2 has been won,the odds are then one in nine for the remaining players?

depends on the type of cake

Original Poster Banned

barky;6900568

you sure about that? surely after the first cake in question 2 has been … you sure about that? surely after the first cake in question 2 has been won,the odds are then one in nine for the remaining players?

this is what my issue is that the chance of winning the first cake in Q2 is 1/10 and the probability of winning the second cake is 1/9 but what is the probability of winning a cake?

raptorcigs;6900606

depends on the type of cake

Mississippi mud pie.

2nd.
1 chance in 10
then 1 chance in 9
overal, a 2 in 9.5 percent chance, or effectively, 1 in 4.75.

or, sod all chance cos by the time you've all worked it out, I've eaten the cake.

surely if they draw the winner of the first cake its 1 in 10 then the second one is 1 in 9

ROKO;6900623

this is what my issue is that the chance of winning the first cake in Q2 … this is what my issue is that the chance of winning the first cake in Q2 is 1/10 and the probability of winning the second cake is 1/9 but what is the probability of winning a cake?

None, usually a fix and the old lady from the Womens Institute will have hoovered it down with her earl grey :whistling:

Original Poster Banned

Jumpingphil;6900564

Q1 10 people 1 cake, probability is 1 in 10.Q2 10 people 2 cakes, … Q1 10 people 1 cake, probability is 1 in 10.Q2 10 people 2 cakes, probability is 2 in 10 = 1 in 5.Alternate answers.Q1 It's a dead certainty that one person will win a cake.Q2 It's also a dead certainty that one person will win a cake but they might be very lucky and win another one too.

for the second question if the person wins the cake they can not win the second cake also.

the long and the short of it from a teachers point of view is that there are several answers for each question as the question itself in ambiguous:

1) 1/10 or 100% depending on how the question is interpreted
2) 0% (as either 1 person has 2 or 2 people have 1) or 19/90 chance based on a 1/10 chance becoming a 1 in 9 chance

raptorcigs;6900606

depends on the type of cake

harlzter;6900632

Mississippi mud pie.

Then I should win all 3 cakes.

hth

Surely if it takes too long to work out, the cake will have gone off and nobody will want it!