Question

question

Answer 1

a) 6435

Answer 2

ok what abt (b) 2)

Answer 3

b2) would be 12c5 - 9c5 .. total number of ways of selection - number of ways when he selects no book from the author ..

Answer 4

:D:D

Answer 5

b) 1) 792

Answer 6

do u know how to do the rest? i mean c

Answer 7

okk c1) would be (26C2 - 26) * (899) * 26
C2) would be 9/899

Answer 8

_ _ _ _ _ _
first two spaces can be filled in
7*6 =42 ways
the three no.s = 9*10*10=900 ways
last letter =19 ways
so total no. of combinations 42*900*19

2nd part
all three no. same= 9*1*1=9 ways
combinations with all three no.s same=42*9*19
probability= 9/900=1/100

Answer 9

don't you have answers??

Answer 10

unfortunately no

Answer 11

What does between 100 and 899 means? Interval is closed or open?

Answer 12

how is 100 to 999- 899 no.s
it's 900 no.s

Answer 13

ohh i didnt see the restriction on letters ..

but the concept remains the same .. :)

Answer 14

guys im sorry i dont really understand this i havent taken it ever , i just want to teach it to someone, so if u can show me the way

Answer 15

I second ash's answer, it seems correct.

Answer 16

@shaan,>> c1) would be (26C2 - 26) * (899) * 26c1) would be (26C2 - 26) * (899) * 26

I still don't know why are you multiplying by 26 in the last case.

Answer 17

I messed it .. I didn't see that there were restrictions on number of letters (I assumed they were 26) ...

Answer 18

ah fine then :)

Answer 19

do the first two letters have to be different?

Answer 20

btw ash's answer assumes that the first two letter is different.

Answer 21

that is why i asked

Answer 22

can we make two assumptions? does it mean it has two answers?

Answer 23

Good point zarkon, it's not clear from the problem statement, however as this is PIN i have a feeling that it should be 7*7.

Yes lala, answer would be different.

Answer 24

Thankyou guys you are all awesome !!!!!!