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Box and ball Probability | B.Stat Objective TOMATO Problem 59

A box contains 100 balls of different colours 28 red 17 blue 21 green 10 white 12 yellow 12 black. The smallest number n such that any n balls drawn from the box will contain at least 15 balls of the same colour is Subscribe to Cheenta at Youtube

Try this problem from I.S.I. B.Stat TOMATO Objective Problem based on Box and ball Probability.

Box and ball Probability ( B.Stat Objective Problem )


A box contains 100 balls of different colours 28 red 17 blue 21 green 10 white 12 yellow 12 black. The smallest number n such that any n balls drawn from the box will contain at least 15 balls of the same colour is

  • 8
  • 77
  • 11
  • 10

Key Concepts


number Series

Logic

Integers

Check the Answer


But try the problem first…

Answer: 77

Source
Suggested Reading

B.Stat Objective Problem

Challenges and Thrills of Pre-College Mathematics by University Press

Try with Hints


First hint

28 -15 gives 13 and 17-15 gives 2 and 21 -15 gives 6 rest are less than 15

Second Hint

then 100 -13=77 and 100-2=98 and 100-6= 94

Final Step

then smallest number= 77

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