Question:medium
A box contains 5 white balls, one red ball and 4 black balls. If three balls are drawn at random, then the probability of getting no red ball is
A box contains 5 white balls, one red ball and 4 black balls. If three balls are drawn at random, then the probability of getting no red ball is
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Logic Tip: Alternatively, use the direct sequential probability method without combinations. The probability of the first ball not being red is $\frac{9}{10}$. The second is $\frac{8}{9}$. The third is $\frac{7}{8}$. Multiply them together: $\frac{9}{10} \times \frac{8}{9} \times \frac{7}{8} = \frac{7}{10}$. This avoids calculating factorials entirely!
Updated On: Apr 27, 2026
- $\frac{1}{10}$
- $\frac{3}{10}$
- $\frac{7}{10}$
- $\frac{9}{10}$
- $\frac{3}{5}$
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The Correct Option is C
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