Home
Class 10
MATHS
A box contains 90 discs which are num...

A box contains 90 discs which are numbered from 1 to 90. If one discs is drawn at random from the box, find the probability that it bears (i) a two digit number (ii) a perfect square number (iii) a number divisible by 5.

Text Solution

Verified by Experts

Total number of disc in a box , n(s) = 90
(i) Let `E_(1)`= Evernt of selecting a two-digits number = `{10,11,......90}`
` " "n(E_(1)) = 81`
Probability of geting a two-digit number = `(n(E_(1)))/(n(E_(2))) = (81)/(90) = (9)/(10)`
(ii) Let `E_(2)` = Event of selecting a number divisibel by 5
`= { 5,10,15,20,25,30,35,40,45,50,55,60,65,70,75,80,85,90}`
`therefore " "n(E_(3)) = 18`
`therefore" "` Required probability `= (n(E_(3)))/(n(S)) = (2)/(6) =(1)/(3)`
Promotional Banner

Topper's Solved these Questions

  • PROBABILITY

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise|29 Videos

  • PROBABILITY

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Very Short Answer/short Answer Questions|16 Videos

  • PROBABILITY

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Very Short Answer/short Answer Questions|16 Videos

  • POLYNOMIALS

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Long Answer Questions|4 Videos

  • QUADRATIC EQUATIONS

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Long Answer Questions|6 Videos

Similar Questions

Explore conceptually related problems

A box contains 90 discs, numbered from 1 to 90. If one disc is drawn at random from the box,find the probability that it bears a prime number < 23.

A bag contains cards which are numbered from 2 to 90. A card is drawn at random from the bag. Find the probability that it bears (i) a two digit number (ii) a number which is a perfect square

A bag contains 100 identical marble stones which are numbered from 1 to 100. If one stone is drawn at random from the bag, find the probability that it bears a number divisible by 4.

A bag contains 100 identical marble stones which are numbered from 1 to 100. If one stone is drawn at random from the bag, find the probability that it bears : (iii) a number divisible by 5.

A bag contains 100 identical marble stones which are numbered from 1 to 100. If one stone is drawn at random from the bag, find the probability that it bears a perfect square number.

A bag contains 100 identical marble stones which are numbered from 1 to 100. If one stone is drawn at random from the bag, find the probability that it bears : (iv) a number divisible by 4 or 5.

A bag contains 100 identical marble stones which are numbered form 1 to 100. If one stone is a drawn at random from the bag, find the probability that it bears (i) a number divisible by 4 or 5 ,(ii) a number divisible by 4 and 5.

A bag contains 100 identical marble stones which are numbered from 1 to 100. If one stone is drawn at random from the bag, find the probability that it bears : (v) a number divisible by 4 and 5.

Cards numbered from 11 to 60 are kept in a box. If a card is drawn at random from the box, find the probability that the number on the drawn cards is (i) an odd number (ii) a perfect square number

A box contains 90 discs, numbered from 1 to 90. If one disc is drawn at random from the box, the probability that it bears a prime number less than 23, is 7/(90) (b) (10)/(90) (c) 4/(45) (d) 9/(89)