**2020-Apr-03**

**Ex: In a two digit number, unit digit is 2 more than the ten's digit. Four times of the sum of digit is 3 less than the number. What is the number ?**

(A) 20

(B) 36

(C) 35

(D) 50

**Trick:**

Let the two digit number be 10x + y

10x + y

y = x +2

y –x = 2 ....(I)

(y+x) 4 = 10x + y – 3

4x +4y = 10x + y–3

6x –3y = 3 ........ (II)

From eq. (I) and (II)

x = 3

y = 5

So, number = 35

**2020-Apr-02**

**Ex: Excluding stoppages, the speed of a bus is 54 km/hr and including stoppages, it is 45 km/hr, for how many minutes does the bus stop per hour?**

A) 12 minutes

B) 8 minutes

C) 10 minutes

D) 5 minutes

**Trick:**

Stopping per hour = 54 − 45 / 45 × 60 = 9 / 45 * 60 = 12 min.

**2020-Apr-01**

**Ex: Two trains with their speeds in the ratio of 3: 4 are going in opposite directions along parallel tracks. If each takes 9 seconds to cross a telegraph post, then the time taken by the trains, to cross each other completely, will be:**

(A) 18 seconds

(B) 12 seconds

(C) 9 seconds

(D) 3 seconds

**Trick:**

L1/3k = 9

L1 = 27 k

and

L2/4k = 9

L2 = 36 k

Now, Required time = (L1 + L2)/ (3k + 4k) = 9 seconds

**2020-Mar-31**

**Ex: A sum of money at simple interest amount to Rs.8118 in 3 years and to Rs.9449 in 4 years. The sum is-**

(A) Rs.4135

(B) Rs.4125

(C) Rs.4120

(D) Rs.4130

**Trick:**

Simple interest = 9449 – 8118 = Rs.1331

Simple interest in 3 years = 3 × 1331

= Rs.3993

Sum = 8118 – 3993 = Rs.4125

**2020-Mar-30**

**Ex: 15 movie theatres average 600 customers per theatre per day. If six of the theatres close down but the theatre attendance stays the same, the average daily attendance per theatre among the remaining theatres is**

(A) 1100

(B) 1200

(C) 900

(D) 1000

**Trick**:

Total customers in 15 movie theatres = 15 × 600 = 9000

Total customers in (15 – 6 = 9) movie theatres now = 9000

Required average number = 9000 ÷ 9 = 1000

**2020-Mar-27**

**Ex: The monthly salaries of two persons in the ratio 8:9. If each receives an increase of Rs. 20 in the salary, the ratio becomes 25:28. Find their salaries.**

A. 500, 560

B. 400, 540

C. 550, 600

D. 480, 540

**Trick:**

(8x + 20) / (9x + 20) = 25/28

=> x = 60

8x= 8 * 60 = 480 and 9x= 9 * 60 = 540

**2020-Mar-26**

**Ex: Water flows into a tank which is 200 m long and 150 m wide, through a pipe of cross-section (0.3m x 0.2m) at 20 km/h. In what time will the water level be 8m?**

(A) 250

(B) 200

(C) 450

(D) 350

**Trick:**

Volume of water collected in the tank in 11 hour

⇒0.3×0.2×20×1000 = 1200 m cubic

If after t hours, the water is at height of 8m,

1200t = 200×150×8

⇒t = 200 Hours.

**2020-Mar-25**

**Ex: The sum of the squares of 3 consecutive odd numbers is 251. Then find the sum of the numbers.**

(A) 9

(B) 15

(C) 21

(D) 27

**Trick:**

Let three odd numbers be 2x – 1, 2x + 1, 2x + 3.

(2x – 1)^2 + (2x + 1)^2 + (2x + 3)^2 = 251

12x^2 + 11 + 12x = 251

12x^2 + 12x – 240 = 0

x = 4, – 5

Numbers are = 7, 9, 11

Required sum = 7 + 9 + 11 = 27

**2020-Mar-25**

**Ex: The sum of the squares of 3 consecutive odd numbers is 251. Then find the sum of the numbers.**

(A) 9

(B) 15

(C) 21

(D) 27

**Trick:**

Let three odd numbers be 2x

**2020-Mar-24**

**Ex: A wheel of radius 1.4 m. of a vehicle makes 40 revolutions in 1 min. What is the speed of the vehicle?**

(A) 21.12 km/h.

(B) 19.6 km/h.

(C) 22.7 km/h.

(D) 22.4 km/h.

**Trick:**

Distance covered in 1 revolution = 2 * 22/7 * 1.4 = 8.8 m.

Distance covered in 40 revolutions = 40 × 8.8 = 352 m. = 0.352 km.

Time = 1/60 hr.

Speed = 0.352 / 1/ 60 = 21.12 km/h