# The probaility of selecting a red ball at random from a jar that contains only red,blue and orange ball is 1/4.The probability of selecting a blue ball at random from the same jar is 1/3.If this jar contains 10 orange balls,then what is the total number of balls in the jar?

let total no of balls be x
then - no. of red balls = x*[1/4]
no. of blue balls = x*[1/3]
no . of orange balls = 10   [given]
so    x = x[1/4] +x[1/3] + 10
= x/4 + x/3 +10
=[3x + 4x]/12 +10
= 7x / 12 +10
x  =[7x + 120]12
  x = 7x +120
12x = 7x + 120
12x -7x =120
5x =120
x =120/5
x =24
so total balls =24

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thankssss
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probability of red ball ( 1/4)

probability of blue ball ( 1/3 )

total orange balls = 10

now

probability of orange ball = 1 - ( 1/4 ) - ( 1/3 )   [ all the probabilities sum up to 1 ]

let total balls be x

1 - ( 1/4 ) - ( 1/3 ) = [ 12 - 3 - 4 ] / 12

= 5 / 12

5x/12 = 10 [ probablity of orange ball is no of orange balls / total balls ]

=> x = 12*10 / 5 = 24 ....

hope this was simpler :)

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Thanks.
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I have also got the same....
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Your Intelligence is my common sense
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thank u

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Thanku
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the probability of selecting a red ball at random from a jar that contains onlyred, and orange balls is 1/4.the probability of selecting a ball at random from the jar is 1/3 .if the jar contains 10 orange balls, find the total number of balls in the jar
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Ans:24
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