Advertisements
Advertisements
Question
A bag contains 15 balls, out of which some are white and the others are black. If the probability of drawing a black ball at random from the bag is `2/3`, then find how many white balls are there in the bag.
Solution
Total number of balls 15
Probability of drawing a black ball at random is `2/3`
probability of black ball + probability of white ball = 1
Probability of white ball = 1- probability of black ball
Probability of drawing a white ball = `1 - 2/3 = 1/3`
Therefore, the number of white balls = `15 xx 1/3 = 5`
APPEARS IN
RELATED QUESTIONS
A bag contains 25 cards numbered from 1 to 25. A card is drawn at random from the bag. Find the probability that the number on the drawn card is:
(i) divisible by 3 or 5
(ii) a perfect square number
The probability of selecting a rotten apple randomly from a heap of 900 apples is 0.18. What is the number of rotten apples in the heap?
A box contains cards bearing numbers from 6 to 70. If one card is drawn at random from the box, find the probability that it bears
(i) a one digit number.
(ii) a number divisible by 5.
(iii) an odd number less than 30.
(iv) a composite number between 50 and 70.
A box contains 80 discs which are numbered from 1 to 80. If one disc is drawn at random from the box, find the probability that it bears a perfect square number.
A box contains 20 cards numbered from 1 to 20. A card is drawn at random from the box. Find the probability that the number on the drawn card is divisible by 2 or 3
In a bag there are 44 identical cards with figure of circle or square on them. There are 24 circles, of which 9 are blue and rest are green and 20 squares of which 11 are blue and rest are green. One card is drawn from the bag at random. Find the probability that it has the figure of green colour
In a bag there are 44 identical cards with figure of circle or square on them. There are 24 circles, of which 9 are blue and rest are green and 20 squares of which 11 are blue and rest are green. One card is drawn from the bag at random. Find the probability that it has the figure of green colour
A die is thrown once. What is the probability of getting an odd number?
A die is thrown once. Find the probability of getting a number less than 3.
The probability of getting an even number, when a die is thrown once is
If a two digit number is chosen at random, then the probability that the number chosen is a multiple of 3, is
A box contains 25 cards numbered from 1 to 25. A card is drawn at random from the bag. Find the probability that the number on the drawn card is divisible by 2 or 3.
A piggy bank contains hundred 50 p coins, seventy ₹1 coin, fifty ₹2 coins and thirty ₹5 coins. If it is equally likely that one of the coins will fall out when the bank is turned upside down, what is the probability that the coin will not be a ₹5 coin?
A game consists of tossing a one-rupee coin three times, and noting its outcome each time. Find the probability of getting three heads.
A game consists of tossing a one-rupee coin three times, and noting its outcome each time. Find the probability of getting at least two tails.
A father's age is three times the sum of the ages of his two children. After 5 years his age will be two times the sum of their ages. Find the present age of the father.
Two coins are tossed together. Find the probability of getting: no head
In a family having three children, there may be no girl, one girl, two girls or three girls. So, the probability of each is `1/4`. Is this correct? Justify your answer
Which of the following is not a random experiment?
Playing cards now the following cards are added to the above cards:
What is the probability of Suhail winning now? Reshma wins if she picks up a 4. What is the probability of Reshma winning?
[Queen, King and Jack cards are called face cards.]
