A box contains 4 white balls, 5 black balls and 7 green balls. in how many ways can 4 balls be drawn from the box, if at least one white ball, one black ball and one green ball is to be included in a draw?
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no. of white balls=4
no. of green ball's=7
no. of black balls=5
p(at least on white ball) = 4C1×4C1×4C1×4C1
p(one black ball)= 5C1
p(one green ball)=7C1
TOTAL BALLS=16
P(A)=4×4C1+7C1×5C1×2×4C1+3×4C1×7C1+3×4C1×5C1
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16C4
no. of green ball's=7
no. of black balls=5
p(at least on white ball) = 4C1×4C1×4C1×4C1
p(one black ball)= 5C1
p(one green ball)=7C1
TOTAL BALLS=16
P(A)=4×4C1+7C1×5C1×2×4C1+3×4C1×7C1+3×4C1×5C1
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16C4
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