Question

An integer is chosen at random from the first 200 positive integers. The probability that the integer chosen is divisible by 6 or 8 is:

Solution

Correct option is

1/4

Let E = divisible by 6

      F = divisible by 8

Number divisible by 6 are: 6, 12, 18, 24,….198 i.e.. There are 33 numbers in first 200 positive integers that are divisible by 6.

           

Number divisible by 8 are: 8, 16, 24, 32,….200 i.e.. There are 25 numbers in first 200 positive integers that are divisible by 8.

           

Number divisible by 6 and 8 both are: 24,….192. These are 8 numbers in first 200 positive integers that are divisible by both 6 and 8.

           

P(integer is divisible by 6 and 8) = P(E ∪ F) = P (E) + P(F)

              

SIMILAR QUESTIONS

Q1

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Q2

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Q3

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Q4

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Q5

 

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Q6

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Q7

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Q8

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Q9

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Q10

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