Drawing/Selecting/Picking Two/Three/More balls from a Box/Bag/Urn
Problem 1
The probability of getting 2 white and 3 black balls from a bag containing 8 white and 12 black balls is
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Problem 2
What is the probability of getting (i) 2 white balls, (ii) 2 green balls, (iii) one of each colour in draw of two balls from a box containing 3 white and 4 green balls?
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Problem 3
Three balls are drawn at random from collection of 7 white, 12 green and 4 red balls. The probability that each is of different colour is
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Problem 4
A bag contains 3 red, 4 white and 5 blue balls, 2 balls are drawn at random. The probability that they are of different colours is
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Problem 5
In a bag there are ten balls of which three are red. Find the probability that in a draw of two balls (i) both will be red (ii) there will be at least one red ball.
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Problem 6
From a bag containing 4 white and 5 black balls a man draws 3 at random. The odds against all the balls being black is
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Problem 7
Define the Event and identify the number of favourable choices in the following cases which relate to the experiment of drawing balls
| a) | The probability of drawing 3 white and 4 green balls from a bag containing 5 white and 6 green balls if the seven balls are drawn at random simultaneously |
| b) | Three balls are drawn from a bag containing 10 white and 15 red and 5 green balls. Find the probability that a) They are white b) They are red c) They are green |
| c) | A box contains 2 red, 3 blue and 4 black balls. Three black are drawn from the box at random. What is the probability that (i) the three balls are of different colours? (ii) two balls are of the same colour and the third of different colour? (iii) all the balls are of the same colour? |
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Practice Problem 1
A bag contains 8 white and 4 red balls. Five balls are drawn at random. Then the probability that 2 of them are red and 3 white is
Practice Problem 2
What is the probability of getting 3 white balls in a draw of 3 balls from a box containing 5 white and 4 black balls?
Practice Problem 3
A bag contains 6 white, 4 red and 10 black balls. two balls are drawn at random. The probability that they will both be black is
Practice Problem 4
A bag contains 2 red, 3 white and 4 black balls. 2 balls are drawn at random, the probability that they are of different colours is
Practice Problem 5
Show that the odds are 7 to 3 against drawing 2 red balls from a bag containing 3 red and 2 white balls.
Practice Problem 6
In a bag there are 12 balls in which 5 are red. The probability that there will be at least one red ball in a draw of two balls is
Practice Problem 7
In a bag there are 12 balls in which 5 are red. The probability that there will be at least one red ball in a draw of two balls is
Practice Problem 8
A bag containing 3 white, and 3 black and 2 blue balls. Three balls are drawn at random from the bag. Find the probability of drawing three balls of the same colour
Practice Problem 9
A box contains 2 red, 3 blue and 4 black balls. Three balls are drawn from the box at random. What is the probability that two balls are of the colour and the third of different colour?
Author : The Edifier