MBA Exam

How many 4 digit numbers are there whose decimal notation contains not more than 2 distinct digits ?

1) 672
2) 576
3) 448
4) 360

Read Solution (Total 3)

total number of 4-digit numbers is 9000. the 4 digit numbers which have 4 distinct digit is 9*9*8*7=4536
the 4 digit numbers having 3 distinct digit is 9*9*8*6=3888( bcoz 3 different digits can be arranged in 6 ways).so the answer is 9000-4536-3888=576
9 years agoHelpfull: Yes(6) No(0)

answer is 672. plzz some1 solve it for me?
11 years agoHelpfull: Yes(0) No(0)
why 9*9*8*6 in 3 distinct and not for 4 distinct
9 years agoHelpfull: Yes(0) No(0)

MBA Other Question

Three trains P, Q and R shuttle between two stations X and Y, taking 5 hours 50 minutes, 2 hours 55 minutes and 5 hours 45 minutes to travel from X to Y, and 3 hours 50 minutes, 3 hours 55 minutes and 9 hours 45 minutes to travel from Y to X, respectively. The trains P, Q and R stop for exactly 10, 5 and 15 minutes respectively at each of the stations X and Y and have no other stops in between. If all the trains leave station Y simultaneously at 9:00 a.m. on Monday, July 4th, then find the earliest time after that when all the trains will leave station X simultaneously.

1) 3:00 p.m. on Sunday, July 24th
2) 11 a.m. on Thursday, July 7th
3) 4:00 p.m. on Friday, July 15th
4) 9:00 p.m. on Monday, July 11th
5) † Almighty Will Save me †
Mr. Lalchand Rajput says that probability that Yuvraj plays and India wins is 1/4 , Pathan plays and India wins is 1/2 and both plays and India wins is 1/4. He also added that the team has 3/4 chances of win. What is the probability that either Yuvraj or Pathan played, when the team won?

1) 2/3
2) 1/2
3) 1/4
4) 3/128