Question

help plse !anybody can answer this question
One black coloured ball is surrounded by similar balls of red colour and again green colour. This pattern is repeated 10 times. Find the difference between total number of green and red balls.

Answer 1

no

Answer 2

A classroom has 26 rows (From A to Z), each row is divided in three columns and each column has five seats. To enter in the class, four doors (D1, D2, D3 and D4) are available and reaching up to the door two stairs (LH & RH) are available. A student wants to take the seat in the row C, F or P and then in how many ways he can get the seat.

Answer 3

If, (P- 1)/9 = r, where r is triangular no and can be maximum of four digit no. What is the probability that P is a perfect number?

Answer 4

Are these from statistics?

Answer 5

I wouldn't know where to begin

Answer 6

One black coloured ball is surrounded by similar balls of red colour and again green colour. This pattern is repeated 10 times. Find the difference between total number of green and red balls.

Answer 7

I wouldn't know where to begin.

Answer 8

one black is the first question

Answer 9

I've not done these before

Answer 10

A classroom has 26 rows (From A to Z), each row is divided in three columns and each column has five seats. To enter in the class, four doors (D1, D2, D3 and D4) are available and reaching up to the door two stairs (LH & RH) are available. A student wants to take the seat in the row C, F or P and then in how many ways he can get the seat.

Answer 11

this one

Answer 12

26*15=390,15/390+15/390+15/390,45/390,9/78 is it right

Answer 13

What exactly are you having trouble with?

Answer 14

A classroom has 26 rows (From A to Z), each row is divided in three columns and each column has five seats. To enter in the class, four doors (D1, D2, D3 and D4) are available and reaching up to the door two stairs (LH & RH) are available. A student wants to take the seat in the row C, F or P and then in how many ways he can get the seat.

Answer 15

45/390 right?

Answer 16

if u cannot try this problem atleast tis one.If, (P- 1)/9 = r, where r is triangular no and can be maximum of four digit no. What is the probability that P is a perfect number?

Answer 17

@phi @ganeshie8 @Nurali @shamil98

It is 2:30 AM here. I am very tired.

Answer 18

whenever possible u can answer.k u take rest

Answer 19

@ganeshie8 is not responding

Answer 20

If, (P- 1)/9 = r, where r is triangular no and can be maximum of four digit no. What is the probability that P is a perfect number?

wat are the perfect numbers less than 10000 ?

Answer 21

6,28,496,8128

Answer 22

i think 55 is the anwser

Answer 23

probability is always a number between 0 and 1

Answer 24

(55-1)/9=6 is a triangular number

Answer 25

from where u got 55 ?

Answer 26

sry i thought that r is a triangular no so 6 is a triangle no.so i told

Answer 27

(P- 1)/9 = r

here, r is a triangular number, and P is a perfect number.

Answer 28

plug in ur perfect numbers one by one and see how many give u a triangular number

Answer 29

Perrfect numbers less than 10000 : 6, 28, 496, 8128

clearly 6 will not work.
lets test 28 :-
(28-1)/9 = 27/9 = 3 YES, 3 is a triangular number !

Answer 30

can u test remaning two ?

Answer 31

496 is also perfect no but i dont know whether it is a triangular no

Answer 32

we dont care whether 496 is triangular or not

Answer 33

we need to check if (496-1)/9 is triangular or not. ok ?

Answer 34

lets test 496 :-
(496-1)/9 = 495/9 = 55 = 10*11/2 = triangular number !!

Answer 35

ya 55 is a triangular number

Answer 36

next, test 8128 :-
(8128-1)/9 = 8127/9 = 903 = 42*43/2 = triangular number !

Answer 37

so, 28, 496 and 8128 satisfy the given relation that (P-1)/9 = r such that r is a triangular number

Answer 38

yes it satisfies

Answer 39

next, how many triangular numbers are there less than 10000 ?

Answer 40

to find that, you need to solve below :-

n(n+1)/2 < 10000
solving gives n <= 140

Answer 41

so probability = 3/140

Answer 42

see if that makes some sense

Answer 43

yes right

Answer 44

for this question above

Answer 45

A classroom has 26 rows (From A to Z), each row is divided in three columns and each column has five seats. To enter in the class, four doors (D1, D2, D3 and D4) are available and reaching up to the door two stairs (LH & RH) are available. A student wants to take the seat in the row C, F or P and then in how many ways he can get the seat.

Answer 46

here is small trick to get ur questions answered quick by others :-
ask oly ONE question per post :) close the questiona nd start a new thread so that, others get to see and assist u....

Answer 47

I had a look, its bit involved... il work it later ok

Answer 48

post it as new quesiton, lets see if somebody answers.... :)

Answer 49

but no one answered wen i asked hte first q .so i posted many