Question
A jar contains 'z' white balls and 9 black balls. If the
probability of getting a white ball is 4/7, then find the probability of getting different coloured balls when two balls are drawn randomly from the jar.Solution
Total number of balls in the jar = z + 9
So, z/(z + 9) = 4/7
Or, 7z = 4(z + 9)
Or, 7z = 4z + 36
So, z = 12
Total balls = 12 + 9 = 21
Desired Probability = (12C1 × 9C1)/21C2 = (12 × 9)/(21 × 20/2) = 108/210 = 18/35
Statements:
Only a few Playlist are Music.
No Music is Song.
All Song are Lyrics.
Conclusions:
I. All Playlist are Ly...
Statements:
Some reds are blues.
All blues are greens.
Some greens are not yellows.
Conclusions:
I. Some yellows ...
Statements:
All M are K.
All K are J.
All L are J.
No L is a P.
Conclusions: Â Â Â Â Â Â Â Â
I. No K is L...
In the question below some statements are given followed by three conclusions I, II, and III. You have to take the given statements to be true even if ...
In the questions given below there are three statements followed by three conclusions I, II and III. You have to take the three given statements to be...
- Statements:
Only a few Plates are Cups
Some Cups are Saucers
No Saucer is a Spoon
Conclusion:
I. Some Plates are not... Statement:
I) No exam is tough
II) All tough are test
III) Some test are easy
IV) All easy are study
Conclusion...
Statements : No triangle is a square.
Some squares are rectangles.
All rectangles are circles.
Conclusions : I. Some circles are ...
In the question below there are three statements followed by three conclusions I, II, and III. You have to take the three given statements to be true e...
Statements: Some badminton are sports.
No sports is a player.
Conclusions: I. Some badminton are not player.
II. Some player ar...
Relevant for Exams:
