A man crosses a stationary bus in 8 seconds. The same bus crosses a pole in 4 seconds. What is the respective ratio between the speed of the bus and the speed of the man ?
9 : 2
9 : 4
18 : 5
Cannot be determined
None of these
Answer: Option E.
Length of bus / Speed of Man = 8, Length of bus / Speed of Bus = 4
Dividing both we get Speed of bus / Speed of Man = 8/4 = 2 : 1.
As this is not given in any of the options, the answer will be none of these.
An intelligence agency decides on a code of 2 digits selected from 0, 1, 2, …. , 9. But the slip on which the code is hand-written allows confusion between top and bottom, because these are indistinguishable. Thus, for example, the code 91 could be confused with 16. How many codes are there such that there is no possibility of any confusion?
25
75
80
95
None of these
Answer: Option C.
Total number of two digit codes that can be formed is 10 x 10 = 100.
Out of them 0, 1, 6, 8, 9 can create confusion.
Using these five digits total number of two digit numbers that can be made is 5 x 5 = 25.
But out of these 25 numbers 00,11,88,69 and 96 will not make any confusion.
Hence answer is 100 - 25 + 5 =80
A nine digit number is made by using the digits 1,2,3,4,5,6,7,8,9 such that digits can be repeated. Find the probability that this number is divisible by 4?
A report consists of 20 sheets each of 55 lines and each such line consist of 65 characters. This report is retyped into sheets each of 65 lines such that each line consists of 70 characters. The percentage reduction in number of sheets is closest to
20
5
30
35
None of these
Answer: Option A.
The total volume of the matter = (20 x 55 x 65).
Let the number of pages in the new format be n.
Hence the volume will be (65 x 70 x n).
Since the volume remains same we can equate the two and hence n = 15.71 = 16 sheets.
Hence percentage reduction in sheet = 4/20 = 20%.
Three distinct numbers are selected from 1st 100 natural numbers. The probability that all the three numbers are divisible by both 2 and 3 is…
2/1155
4/1155
6/47
56/1155
None of these
Answer: Option B.
A number is divisible by 2 and 3 if it is divisible by 6.
There are 16 multiple of 6 till 100.
⇒ Required probability = 16C3/100C2=4/1155
A bag contains 7 blue balls and 5 yellow balls. If two balls are selected at random, what is the probability that none is yellow?
5/33
5/22
7/22
7/33
7/66
Answer: Option C.
Probability of getting 1st blue ball = 7/12
Probability of getting 2nd blue ball = 6/11
So, probability of getting no yellow ball = 7/12 × 6/11 = 7/22
A die is thrown twice. What is the probability of getting a sum 7 from both the throws?
5/18
1/18
1/9
1/6
5/26
Answer: Option D.
Cases of getting a sum of 7 = (1,6), (2,5), (3,4), (6,1), (5,2), (4,3) = 6
Total cases = 36
Required probability = 6/36 = 1/6
DIRECTIONS for the question 8 to 10: Read the information given below and answer the question that follows.
In a team there are 240 members (males and females). Two-third of them are males. Fifteen percent of males are graduates. Remaining males are non-graduates. Three-fourth of the females are graduates. Remaining females are non-graduates.
What is the difference between the number of females who are non-graduates and the number of males who are graduates?
2
24
4
116
136
Answer: Option C
Males ⇒ 160
Females ⇒ 80
Males graduate ⇒ 24
Males Non-graduate ⇒ 136
Female graduate ⇒ 60
Females non-graduate ⇒ 20
Difference between the number of females who are non-graduates and the number of males who are graduates = 24 – 20 = 4.
What is the sum of the number of females who are graduates and the number of males who are non-graduates?
184
96
156
84
196
Answer: Option E
Sum of the number of females who are graduates and the number of males who are non-graduates = 60 + 136 = 196
What is the ratio between the total number of males and the number of females who are non-graduates?
6 : 1
8 : 1
8 : 3
5 : 2
7 : 2
Answer: Option B.
Total number of males = 160
Number of females who are non-graduates = 20
Required ratio = 160 : 20 = 8 : 1.
Hence, second option is the answer.
