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Probability
A basket contains 6 red balls, 5 blue balls, 4 green balls and 3 white balls. Five balls are to be drawn together at random, then what is the probability that there is at least a ball of each colour?
a. 10/51
b. 5/51
c. 10/17
d. 5/17
Read Solution (Total 18)
-
- required probability={(6*5*4*3c2)+(6*5*4c2*3)+(6*5c2*4*3)+(6c2+5*4*3)}/18c5
=(360+540+720+900)/18*17*14*2
=5/17 - 10 years agoHelpfull: Yes(34) No(2)
- 6c2*5c1*4c1*3c1 + 6c1*5c2*4c1*3c1 + 6c1*5c1*4c2*3c1 + 6c1*5c1*4c1*3c2 =2520
total 18c5
ans 25208568= 5/17 - 10 years agoHelpfull: Yes(23) No(0)
- as we have to draw 5 balls in which at leat 1 ball of each colour should be present..so it can be done in four ways...by selecing 2 balls from one colour and rest 3 from remaining 3 colours...so required probability=
{(6c2*5c1*4c1*3c1)+(6c1*5c2*4c1*3c1)+(6c1*5c1*4c2*3c1)+(6c1*5c1*4c1*3c2)}/18c5
=5/17 - 10 years agoHelpfull: Yes(8) No(0)
- there are total 5 balls selected and we have to select at least one from each color, that leaves that the remaining ball can be of either of 4 colors
there will be 4 cases
case 1 : last ball is red
6c2*5c1*4c1*3c1
case 2 : blue
6c1*5c2*4c1*3c1
and this will go like this for rest 2 cases
now we can select 5 balls from 18 in 18c5 ways
so the required probability will be
(6c2*5c1*4c1*3c1 + 6c1*5c2*4c1*3c1 + 6c1*5c1*4c2*3c1 + 6c1*5c1*4c1*3c2)/18c5
= 5/17
- 10 years agoHelpfull: Yes(5) No(0)
- total reqiured possible ways are (6*5*4*3c2)+(6*5*4c2*3)+(6*5c2*4*3)+(6c2*5*4*3)===>>>360+540+720+900=2520
total ways of selecting 5 balls=18c5=8568
so probability=2520/8568=5/17 - 10 years agoHelpfull: Yes(3) No(0)
- ANSWER ==> 5/17
P(E)= {(6C1*5C1*4C1*3C2)+(6C1*5C1*4C2*3C1)+(6C1*5C2*4C1*3C1)+(6C2*5C1*4C1*3C1)}/18C5 = 2520/8568 = 5/17 - 10 years agoHelpfull: Yes(3) No(0)
- p(e)=(3c2*6c1*5c1*4c1)+(3c1*6c2*5c1*4c1)+(3c1*6c1*5c2*4c1)+(3c1*6c1*5c1*4c2)/(18c5)=10/17 ans....
- 10 years agoHelpfull: Yes(3) No(0)
- probability=[(6C2*5*4*3)+(6*5C2*4*3)+(6*5*4C2*3)+(6*5*4*3C2)]/18C5
on solving =5/17 - 10 years agoHelpfull: Yes(2) No(0)
- probability=((6c2*5c1*4c1*3c1)+(6c1*5c2*4c1*3c1)+(6c1*5c1*4c2*3c1)+(6c1*5c1*4c1*3c2))/18c5
=5/17
- 10 years agoHelpfull: Yes(1) No(0)
- (6c2*5c1*4c1*3c1+6c1*5c2*4c1*3c1+6c1*5c2*4c1*3c1+6c2*5c1*4c1*3c1)/18c5=5/17
- 10 years agoHelpfull: Yes(1) No(0)
- Ans=c
n(s)=18C5=8568
n(a)=6c1*5C1*4c1*3c1*14c1=5040
p9a0=5040/8658 - 10 years agoHelpfull: Yes(1) No(1)
- D
taking 4 cases with 2 balls frm red,blue,green,white resp. in each case nd rest others balls of other clrs - 10 years agoHelpfull: Yes(0) No(0)
- (6c1*5c1*4c1*3c1)(14c1)/18c5=10/17
- 10 years agoHelpfull: Yes(0) No(5)
- As only 2 types of socks exist. Let us assume for simplicity 5pair are red and 5pair are blue.
total socks 20 and we have to select 3. then n(s)=20C3
we can select one pair of red sock and 1 blue sock or 1 pair of blue sock and 1 red sock
two combination possible
hence (10C2*10C1+10C2*10C1)/20C3
ANS 900/1140=15/19 - 10 years agoHelpfull: Yes(0) No(3)
- 6*5*4*3*14c1/18c5
- 10 years agoHelpfull: Yes(0) No(0)
- 6C2*5*4*3+6*5C2*4*3+6*5*4C2*3+6*5*4*3C2/18C5
=5/17 - 10 years agoHelpfull: Yes(0) No(0)
- {(6*5*4*3c2)+(6*5*4c2*3)+(6*5c2*4*3)+(6c2+5*4*3)}/18c5
=(360+540+720+900)/18*17*14*2
=5/17 - 10 years agoHelpfull: Yes(0) No(0)
- can any one explain why the following process is not correct??
(6c1*5c1*4c1*3c1)(14c1)/18c5=10/17
- 9 years agoHelpfull: Yes(0) No(0)
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