Civil Engineering - Online Test
Q1. Which one of the following does NOT equal 
Answer : Option A
Explaination / Solution:
If matrix B is obtained from matrix A by replacing the 1th row by itself plus k times the mth row, for 1 ≠ m then det(B)=det(A). With this property given matrix is equal to the matrices
given in options (B),(C) and (D).
Q2. Suppose p is number of cars per minute passing through a certain road junction between 5
PM and 6PM, and p has a Poisson distribution with mean 3. What is the probability of
observing fewer than 3 cars during any given minute in this interval?
Answer : Option C
Explaination / Solution:
Q3. What is the logical translation of the following statement?
“None of my friends are perfect.”
Answer : Option D
Explaination / Solution:
“None of my friends are perfect”
Q4. Out of all the 2-digit integers between 1 and 100, a 2-digit number has to be selected at
random. What is the probability that the selected number is not divisible by 7?
Answer : Option D
Explaination / Solution:
The number of 2 digit multiples of 7 = 13
∴ Probability of choosing a number
Not divisible by 7 = (90-13)/90 = 77/90
Q5. Find the sum of the expression
Answer : Option B
Explaination / Solution:
The expression can be written as
Q6. The current erection cost of a structure is Rs. 13,200. If the labour wages per day increase by
1/5 of the current wages and the working hours decrease by 1/24 of the current period, then
the new cost of erection in Rs. is
Answer : Option B
Explaination / Solution:
Let ‘W’ be the labour wages, and ‘T’ be the working hours.
Now, total cost is a function of W × T
Increase in wages = 20%
∴ Revised wages = 1.2 W
Decrease in labour time = (100/24)%
∴ Re vised time = (1-(1/24))T = (23/24)T
Re vised Total cost = 1.2 × (23/24)WT = 1.15WT
= 1.15 × 13200 = 15180
Q7. he ratio of male to female students in a college for five years is plotted in the following line
graph. If the number of female students in 2011 and 2012 is equal, what is the ratio of male
students in 2012 to male students in 2011?
Answer : Option C
Explaination / Solution:
Take number of female students in 2011=100
∴ Number of male in 2011=100
No. of female in 2012=100
No. of male in 2012=150
Ratio = 150/100 = 1.5:1
Q8. Let X and Y be finite sets and f : X → Y be a function. Which one of the following
statements is TRUE?
Answer : Option D
Explaination / Solution:
Q9. Which one of the following statements is TRUE about every n × n matrix with only real
eigenvalues?
Answer : Option A
Explaination / Solution:
If the trace of the matrix is positive and the determinant of the matrix is negative then atleast
one of its eigen values is negative.
Since determinant = product of eigen values.
Q10. Consider a hash table with 100 slots. Collisions are resolved using chaining. Assuming
simple uniform hashing, what is the probability that the first 3 slots are unfilled after the first
3 insertions?
Answer : Option A
Explaination / Solution:
