Algebra> probability...

Five horses are in a race. Mr. A selects two of the horses at random and bets on them. The probability that Mr. A selected the winning horse is_________________.

shiva S , 13 Years ago

Grade 11

7 Answers

Aman Bansal

Dear Shiva,

The probability of winning is 2/5

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Last Activity: 13 Years ago

upender surepally

2/5

Approved

Last Activity: 13 Years ago

Shaurya Gupta

total no of options - 5

selected options - 2

therefore probability that Mr.A selected the winning horse - 2/5

Last Activity: 13 Years ago

Aravind Bommera

The probability of winning is 2/5

Last Activity: 12 Years ago

ishaan agarwal

This question came in aieee 2003. 2/5 is not in the option only.

Last Activity: 11 Years ago

R Surya Narayan

In total there are 5 horses. out of these Mr A selects two horses. This can be done in $\binom{5}{2}$ (5C2)=10 ways.

Out of the five horses only one horse wins. Let us say Mr A has selected the horse. He has to select one more horse so that his set of two has the winning horse. out of remaining 4 one can be selected in $\binom{4}{1}$ ways.Thus

$n(E)=\binom{4}{1}=4$

$n(S)=\binom{5}{2}=10$

$\Rightarrow P(E)=\frac{n(E)}{n(S)}=\frac{4}{10}=\frac{2}{5}$

Last Activity: 8 Years ago

ankit singh

In total there are 5 horses. out of these Mr A selects two horses. This can be done in 5C2=10 ways.

Out of the five horses, only one horse wins.

Let us say Mr A has selected the horse. He has to select one more horse so that his set of two has the winning horse. out of remaining 4 one can be selected in 4C1=4 ways.

Thus,

In total there are 5 horses. out of these Mr A selects two horses. This can be done in $\binom{5}{2}$ (5C2)=10 ways.

$n(E)=\binom{4}{1}=4$

$n(S)=\binom{5}{2}=10$

$\Rightarrow P(E)=\frac{n(E)}{n(S)}=\frac{4}{10}=\frac{2}{5}$

The probability that Mr.A selected the winning horse is = 104=52In total there are 5 horses. out of these Mr A selects two horses. This can be done in 5C2=10 ways.

Out of the five horses, only one horse wins.

Let us say Mr A has selected the horse. He has to select one more horse so that his set of two has the winning horse. out of remaining 4 one can be selected in 4C1=4 ways.

Thus,