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A boy forgets the last two digits of his...

A boy forgets the last two digits of his friend's telephone number. He however remembers that they are different numbers. If he dials at random, the probability that he dials correctly is

A

`(1)/(100)`

B

`(1)/(90)`

C

`(1)/(10)`

D

`(8)/(9)`

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The correct Answer is:
B
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AAKASH SERIES-PROBABILITY-Exercise-II
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  2. If a number x is selected from natural numbers 1 to 100, then the prob...

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  3. A boy forgets the last two digits of his friend's telephone number. He...

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  4. Five horses are in a race. Mr. A selects two of the horses at random ...

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  5. From 6 men and 4 women a committee of 5 members is to be formed. The p...

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  6. 24 boys are divided randomly into two equal groups. The probability th...

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  7. A determinant is chosen at random from the set of all determinants of ...

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  8. Let x be a non-zero real number. A determinant is chosen from the set ...

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  9. A committee of five is to be chosen from a group of 8 people which inc...

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  10. Two players A and B each toss 10 coins. The probability that they show...

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  11. From the set of numbers {2,3,4,…..,30} a number is selected at random....

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  12. If a is an integer and a in (-5,30] then the probability that the grap...

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  13. If A,B,C are mutually exclusive and exhaustive events such that P(A)=2...

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  14. A college student has to appear for two examinations A and B. The prob...

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  15. If P(A)=0.7, P(B)=0.4 then the interval in which P(AnnB) lies is

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  16. Events A,B,C are mutually exclusive events such that P(A)=(3x+1)/(3), ...

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  17. If a number is a selected at random from first 100 natural numbers the...

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  18. If 3 dice are rolled then the probability of getting different numbers...

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  19. The odds against an event are 5 to 2 and the odds in favour of another...

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  20. In a class there are 60 boys and 40 girls. Among the boys as well as g...

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