Question
A bag contains 7 orange balls, 8 red balls and 5 black
balls. Three balls are drawn at random. Find the probability that at least two balls are red.Solution
Total = 7 + 8 + 5 = 20
Required probability = (Two red and one other) + (Three red)
= 3 × [(8/20) × (7/19) × (12/18)] + (8/20 × 7/19 × 6/18)
= (2016/6840) + (336/6840)
= (2352/6840) = (98/285) = 5/57
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The IUPAC name of the compound CH₃ -CH₂ -CH₃ is-
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How many carbon atoms are present in a molecule of propene?
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The combining power of an element is called its:
Who discovered the atomic nucleus?
Based on the periodic trends for ionization energy, which element has the highest ionization energy?
Which fuel has the highest calorific value?
