Question
A alone can complete 70% of a work in 21 days while B
takes 15 days more than A to complete it. If B and C together can complete the work in 20 days, then find the time taken by C alone to complete the same work.Solution
Time taken by A alone to complete the entire work = 21/0.7 = 30 days Time taken by B alone to complete the entire work = 30 + 15 = 45 days Let the total work = L.C.M of 30, 45 and 20 = 180 units Then, efficiency of B = (180/45) = 4 units/day Combined efficiency of B and C = (180/20) = 9 units/day So, efficiency of C alone = 9 – 4 = 5 units/day So, time taken by C alone to complete the entire work = (180/5) = 36 days
If A and B are events such that P(A|B) = P(B|A), then which of the following is true
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 is trying to break a bulb by throwing balls at it. If he hits the bulb 5 times in every 7 throws and bulb breaks 3 times out of 15 hits, then find the...
A box contains 10 red balls, 12 green balls, and 8 blue balls. Two balls are drawn at random. What is the probability that both balls drawn are either r...
Two cards are drawn at random from a standard deck of 52 cards. What is the probability of drawing at least one queen?
Two cards are drawn together from a pack of 52 cards. The probability that one is a club and one is a diamond?
Roger Federer gets a chance of 60% to win 1st set of tennis and Andy Murray gets a chance of 55% to win 2nd set of tennis. In what Percent of cases are ...
A vessel contains 5 red, ‘x’ green and 3 blue ribbons. If two ribbons are drawn from the vessel randomly, then the probability of getting a red and ...
Two hats are picked at random, what is the probability that one is blue and one is yellow?
- In how many ways can the letters of the word "MATHEMATICS" be arranged, and what is the probability that all the consonants in these arrangements always ap...