# Quantitative Aptitude: Probability Questions – Set 16

1. A bag contains 3 ruby balls and 8 blue balls and another bag contains 5 ruby balls and 7 blue balls.One ball is drawn at random from either of the bag.Find the probability that the ball is ruby?
94/265
96/254
98/252
91/264
None of these
Option D
(1/2) * (3/11) + (1/2) * (5/12)

2. In a race of 12 bikes,the probability that bike A will win is 1/5 and of bike B is 1/6 and that of bike C is 1/3.Find the probability that only one of them won the race?
5/9
6/7
7/10
7/12
None of these
Option C
1/5+1/6+1/3=7/10

3. P and Q are two friends sitting in a circular arrangement with 8 other friends.Find the probabiity that both P and Q sit together?
1/5
2/7
2/9
3/10
None of these
Option C

4. From a pack,if 3 cards are drwan at random one after the other with replacement,find the probability that one is ace,one is jack and one is queen?
15/7725
16/5525
20/5874
25/9425
None of these
Option B

5. A box contains 50 toffees,numbered from 1 to 50.If three toffees are drawn at random at replacement.What is the probability that sum of yhe numbers arre odd?
1/3
1/2
1/5
1/7
1/6
Option B

6. A pack contains 4 ruby,5 grey and 6 white balls.If one ball is drwan at random,find the probability that is neither ruby nor white?
1/2
1/5
1/6
1/3
None of these
Option D
=5C1/15C1

7. Find the probability that in leap year,the number of Momdays are 53?
1/7
2/7
3/7
4/7
5/7
Option B

8. A bag contains 5 blue and 8 yellow balls.Four balls are drwan at random and not replaced.Wat is the probability that they are of different colors alternatively?
52/487
56/429
54/481
51/529
None of these
Option B

9. 12 students are seating together in a circular table.Find the probability that 3 particular student are always seated together?
3/55
1/55
4/55
5/42
None of these
Option A
Probability=(9!*3!) /11!

10. In how many different ways “FAVOUR” can be arranged?
720 ways
820 ways
840 ways
700 ways
None of these
Option A
6*5*4*3*2*1