How many four digit numbers can be made using 1-2-3-4?
Answer:
it is a permutation problem,
if the number can use repeatedly, it will become 4 x 4 x 4 x 4 = 256
four digit numbers, if the number only can used once, than the answer is
4 x 3 x 2 x 1 = 24 four digit number
I have one question!!
ReplyDeleteSuppose A and B are two persons arrive at same time between 5pm to 6pm.They both arrive at random times within 1 hours and stay for 5 mins.Since they only go one time.what is the probability that they will meet during that hours?
Mostly Asked by MNC Companies!!