The correct answer is option 2 i.e. Rs. 18381.

We know, the interest rate is 11% and difference in CI and SI for 2 years is Rs. 605.

Or,

(P × 11 × 11)/(100 × 100) = 605

⇒ P = 6050000/121 = Rs. 50000

Now, interest earned in 3 years:

⇒ (50000 × 1.11 × 1.11 × 1.11) - 50000

⇒ 68381.55 - 50000

⇒ Rs. 18381.55 = Rs. 18381 (Approx.)

The correct answer is option 3 i.e. 2 : 38 PM.

The time interval between the successive rings when they ring together = LCM of (25, 20, 30)

⇒ 300 minutes

⇒ 5 hours

If it rang first at 9: 38 AM then, they will ring after 5 hours = 2 : 38 PM

The correct answer is Option 2 i.e. 50 kg.

Average = Sum of weight of students/total students

Let the number of students in class A, class B, and class C = x, 2x, and 3x

The sum of the weight of students in class A = 54 × x = 54x

The sum of the weight of students in class B = 48 × 2x= 96x

The sum of weight of students in class C = 50 × 3x = 150x

The sum of total weight of students in all the class

⇒ 54x + 96x + 150x = 300x

The total number of students = x + 2x + 3x = 6x

The average weight of students of all classes together

⇒ 300x/6x = 50 kg

The correct answer is Option 4 i.e. 9.

If a number is divisible by 9, then the sum of digits of the number should be divisible by 9

Given number N27 = N + 2 + 7 = N + 9

Here, if we take N = 0 the sum will be 9 which is divisible by 9

But, if take 0 then the number formed will not be the three-digit number

So, we take N = 9 

Then 9 + 9 =18 which is divisible by 9

The correct answer is Option 2 i.e. 20.

Let the ages of father, mother, and son earlier be 8x, 7x, and 2x respectively

After 16 years,

Age of father = (8x + 16)

Age of mother = (7x + 16)

Age of son = (2x + 16)

Age of his wife = (2x + 16) – 2 = (2x + 14)

Sum of ages of father and mother = (8x + 16) + (7x + 16) = (15x + 32)

Sum of ages of son and his wife = (2x + 16) + (2x + 14) = (4x + 30)

⇒ (15x + 32)/(4x + 30) = 2/1

⇒ (15x + 32) = (8x + 60)

⇒ 7x = 28

⇒ x = 4

Age of mother when the son was born = Age of mother – Age of son

⇒ 7x – 2x = 5x

⇒ 5 × 4 = 20 years

The correct answer is option 2 i.e. 3.5 years.

Simple interest = (principal × rate × time)/100

Amount = Principal + S.I

Given, A = 1728

P = 1350

R = 8%

Time = {(A - P) × 100}/(P × r)

= {(1728 - 1350) × 100}/1350 × 8

= (378 × 100)/(1350 × 8)

= 3.5 years

The correct answer is Option 3 i.e. 8

Remainder Theorem: If a polynomial is divided by (x + a), and remainder is R, then f(-a) = R

Polynomial = x⁴ - 4x³ - 7x² + kx - 1

Dividend = (x + 2)

Remainder = 3

According to remainder theorem,

f(-2) = 3

⇒ (-2)⁴ - 4 × (-2)³ - 7 × (-2)² - 2 × k - 1 = 3

⇒ 16 + 32 - 28 - 2k - 1 = 3

⇒ -2k = -16

⇒ k = 8

The correct answer is option 4 i.e. 2400.

Let x + 4 = y

Marked price = Rs.4800

Selling price = Rs 3225.6

Let the total discount percentage be d

⇒ (100 - d) % of 4800 = 3225.6

⇒ (100 - d) = 67.2

⇒ d = 32.8%

Successive discount = a + b + ab/100

Two discounts will be y and y + 4

Total discount = y + y + 4 - y(y + 4)/100

⇒ 200y + 400 - y² - 4y = 32.8 × 100

⇒ y² - 196y + 2880 = 0

⇒ y = 16, 180 (16 is possible)

⇒ x + 4 = y

⇒ 16 = x + 4

⇒ x = 12

Value of 4x + 2 = 50

After 50% discount, SP = 4800 × 1/2 = Rs.2400

The correct answer is Option 2 i.e. 8

(1369)^1/2 - (2197)^1/3+ 276 - ?² = (4225)^1/2 + 171

⇒ 37 - 13 + 276 - ?² = 65 + 171

⇒ 24 + 276 – (?)² = 236

⇒ 300 – 236 = (?)²

⇒ ? = 8

The correct answer is Option 2 i.e. 7.

If the sum of the digit of a given number is divisible by 9 then, the number is divisible by 9.

The given number is 418X367,

the sum of the digit of the number is 4 + 1 + 8 + X + 3 + 6 + 7 = 29 + X

The smallest whole number X will be 7 then the sum is divisible by 9.

So, the possible value of X is 7