Advertisements
Advertisements
प्रश्न
In a box there are 20 non-defective and some defective bulbs. If the probability that a bulb selected at random from the box found to be defective is `3/8` then, find the number of defective bulbs
उत्तर
Let the number of defective bulbs be “x”
Sample space (S) = 20 + x
n(S) = 20 + x
Let A be the event of getting to be defective
n(A) = x
P(A) = `("n"("A"))/("n"("S"))`
⇒ `3/8 = x/(20 + x)`
⇒ 8x = 3(20 + x) = (60 + 3x)
⇒ 8x – 3x = 60
⇒ 5x = 60
⇒ x = `60/5`
⇒ x = 12
Number of defective bulbs = 12
APPEARS IN
संबंधित प्रश्न
Write the sample space for tossing three coins using tree diagram
Write the sample space for selecting two balls from a bag containing 6 balls numbered 1 to 6 (using tree diagram).
If A is an event of a random experiment such that `"P"("A"):"P"(bar"A")` = 17 : 15 and n(S) = 640 then find `"P"(bar"A")`
At a fete, cards bearing numbers 1 to 1000, one number on one card are put in a box. Each player selects one card at random and that card is not replaced. If the selected card has a perfect square number greater than 500, the player wins a prize. What is the probability that the second player wins a prize if the first has won?
Three fair coins are tossed together. Find the probability of getting all heads
Three fair coins are tossed together. Find the probability of getting atleast one tail
Three fair coins are tossed together. Find the probability of getting atmost two tails
A bag contains 5 red balls, 6 white balls, 7 green balls, 8 black balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is white
Two customers Priya and Amuthan are visiting a particular shop in the same week (Monday to Saturday). Each is equally likely to visit the shop on any one day as on another day. What is the probability that both will visit the shop on different days?
If a letter is chosen at random from the English alphabets {a, b, …, z}, then the probability that the letter chosen precedes x