In how many ways 4 letters can be posted in two post boxes?
Answer Posted / binesh
I think the robbins way
is right. But i couldnt
under stand why did
he multiply the result
by 2
the chances are
none in the fist box
and all in the other
box=4C0=1
1 in fist and 3 in
second=4C1=4
2 in first and 2 in
second=4C2=6
3 in first and 1 in
second=4C3=4
4 in fist and none in
second=4C4=1
so net chance is
4C0+4C1+4C2+4C3+4C4=16
| Is This Answer Correct ? | 4 Yes | 2 No |
Post New Answer View All Answers
A farmer built a fence around his 17 cows, in a square shaped region. He used 27 fence poles on each side of the square. How many poles did he need altogether?
There are two trees in a lawn. One grows at a rate 3/5 of the other in 4 years. If the total growth of trees is 8 ft. What is the height of the smaller tree after 2 years
A sum 's' is divided into 4 parts. Second person gets Rs 10 more than first.3rd person is Rs 10 more than second, 4th is 10 more than 3rd. How much amount do 1st person get?
If we r terminated at the middle of the program execution in UNIX,wat will happen to the program,it will continue running r terminate r the o/p will be send to ur mail?
12 Blacksox and 12 Whitesox mixed in a box,a pair of sox is picked at a time,in which pick how many pick ,to get the right pair(black&black or white&white)?
In the given quadratic equation, mx2+nx+o=0 .If the ratio of the sum of the roots and the product of roots is 2:7, what can be possible values of b and c?
If the operation,^ is defined by the equation x ^ y = 2x + y,what is the value of a in 2 ^ a = a ^ 3
how to get the system time dynamically in orcle
If x,y,z are chosen frm -3,1/2,2 what is the largest value of (x/y)*z*z
how can i get previous ssc data entry question papers?... if u have any idea pls give me very kindly.....
A man, a woman, and a child can do a piece of work in 6 days. Man only can do it in 24 days. Woman can do it in 16 days and in how many days child can do the same work?
Two trains leaving from two station 50 miles away from each other with constant speed of 60 miles per hour, approaches towards each other on different tracks. if length of each train is 1/6 mile. when they meet How much time they need to pass each other totally ?
15 software functions are there. It is known that atleast 5 of the m are defective. What is the probability that if three functions are chosen and tested, no errors are uncovered.
There are two queues at a discount store billing counter. In the first queue there are a1 customers all with b1 items in their cart, while in the second queue there are a2 customers all with b2 items in their cart. It takes t seconds to process each item and p seconds for each person to pay. A customer wishes to know which queue to join.Which one of these options gives the condition for the first queue to be the better queue to join?
A>B,B>C,C=D,D>E,then which is greatest?