Question
If a tank can be filled by a tap in 20 hours, but due to
an outlet, it actually takes 8 hours longer to fill the tank, find the duration in which the outlet alone would empty the tank?Solution
Let tap βAβ fill the tank and tap βBβ empty the tank. Taking LCM of 20 and 28 = 140 Efficiency of A = 7 Efficiency of (A β B) = 5 Efficiency of B = 7 β 5 = 2 Tap B will empty the tank = 140/2 = 70 So, tap B will empty the tank in 70 hours.
A bag contains 14 Green and 16 Red balls. One ball is drawn at random. What is the probability that the ball drawn is Red?
A bag contains 10 red books, 7 yellow books and 7 green books . 3 books are drawn randomly. What is the probability that the...
A is trying to break a bulb by throwing balls at it. If he hits the bulb 3 times in every 5 throws and bulb breaks 3 times out of 12 hits, then find the...
A person can hit a target 3 times out of 8 shots. If he fires 10 shots, what is the probability that he will hit the target twice
Two cards are drawn at random from a pack of 52 cards. What is the probability that either both are black or both are queens?
A 5-digit number is created using the digits 2, 3, 4, 5, and 6 without repetition. What is the probability that the number is divisible by 5?
The probability of selecting 2 one-rupee coins from a collection of 'a' one-rupee coins and 4 two-rupee coins is 1/3. Determine the probability of rando...
The names of 17 students from section A, 18 students from section B and 19 students from section C were selected. The age of all the 54 students was dif...
There are three boxes βAβ, βBβ and βCβ. Box βAβ contains 6 black and 12 white cubes, box βBβ contains 6black, and 8 white cubes and ...
A box contains only three colors of balls- red, green and blue. What is the minimum number of balls that should be picked from the box to ensure that at...