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What is the probability of picking at least one white ball
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nh8404052006
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If two balls are to be choosen from 3 red balls and 2 white balls, what is the probability of picking at least one white ball?
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parallel_chase
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nh8404052006 wrote:If two balls are to be choosen from 3 red balls and 2 white balls, what is the probability of picking at least one white ball?
at least 1 white = probability of picking 1 white + probability of picking 2 white
Probability of picking 1 white
2C1 * 3C1 / 5C2 = 6/10
Probability of picking 2 white
2C2 / 5C2 = 1/10
total probability = 6/10 + 1/10 = 7/10
Hope this helps.
No rest for the Wicked....
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cramya
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2C1->PICKING 1 WHITE BALL FROM 2
3C1->PICKING 1 RED BALL FROM 3
2C2->PICKING 2 WHITE BALLS FROM 2
5C1->NUMBER OF WAY 2 BALLS CAN BE PCIKED FROM 5
2C1*3C1 + 2C2 / 5C2
= 7/10
(OR)
P(atleast one) = 1 - p(none) where p(none) is pciking red ball first and red ball second
= 1- 3/5*2/4
= 7/10
3C1->PICKING 1 RED BALL FROM 3
2C2->PICKING 2 WHITE BALLS FROM 2
5C1->NUMBER OF WAY 2 BALLS CAN BE PCIKED FROM 5
2C1*3C1 + 2C2 / 5C2
= 7/10
(OR)
P(atleast one) = 1 - p(none) where p(none) is pciking red ball first and red ball second
= 1- 3/5*2/4
= 7/10
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kishore
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If two balls are to be choosen from 3 red balls and 2 white balls, what is the probability of picking at least one white ball?
Answer: probability of picking at least one white ball is
1 - (probability of picking only red ball)
1 - ( 3C2/5C2) = 1- (3/10) = 7/10
Answer: probability of picking at least one white ball is
1 - (probability of picking only red ball)
1 - ( 3C2/5C2) = 1- (3/10) = 7/10
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vittalgmat
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The quickest way to solve probability problems which have "atleast" is to do the 1 - P(something else happening all the time), if that is possible, and most of the times it is possible.
I find this approach very scalable.
just my opinion.
Thanks
I find this approach very scalable.
just my opinion.
Thanks
