Category: Arithmetic/ Basic Math

Q. What is the solution set of the equation: x²+4x+3=0
(A) {1, 3}
(B) {–1, 3}
(C) {1, –3}
(D) {–1, –3}

The answer is: (D) {–1, –3}
Solution

(A) 4 km/hr
(B) 5 km/hr
(C) 6 km/hr
(D) 7 km/hr

The answer is: (D) 7 km/hr
Solution
Total Distance = 9km + 12km = 21 km. And, Total Time = 1 hour 20 + 1 hour 40 = 3 hours. Hence, Average Speed is

(A) 4
(B) 5
(C) 6
(D) 7

The answer is: (B) 5
Solution
Out of 4 options only one is correct. So,

(A) 180
(B) 182
(C) 184
(D) 186

The answer is: (C) 184
Solution
As we know that, Cost + Profit = Selling Price. Hence,

(A) 3-2x
(B) 1-2x
(C) 2x-1
(D) (x+3)/2

The answer is: (D) (x+3)/2
Solution

Q. What is: |2| – |–2| – 2² – (–2)² = ?
(A) –8
(B) –6
(C) –4
(D) –2

The answer is: (A) –8
Solution

(A) 2450
(B) 2500
(C) 2550
(D) 2600

The answer is: (C) 2550
Solution
This is an arithmetic sequence with common difference of 2. The first element is 2, the last element is 100, and total elements (from 2 to 100) are 50. So, a₁ = 2, a_n = 100, d = 2 and n = 50. So, by using the formula for the sum of n elements of an arithmetic sequence, we have

(A) 5000
(B) 5050
(C) 5100
(D) 5150

The answer is: (B) 5050
Solution
These are the first 100 natural numbers (n=100). So, by applying formula for the sum of the first n natural numbers, we have

(A) 21
(B) 22
(C) 23
(D) 24

The answer is: (D) 24
Solution