Tips and Tricks of The Day


Record Limit : 

    2020-Jul-03
Ex: Two men, sitting on the table. One man has 7 eggs and other had 5 eggs. A third man passing by requested them to share their food in return for money. The three of them shared the eggs equally and the third traveller paid the other two a total of Rs 24.Find the difference between the amounts received by first two men?
(A) 12 
(B) 18 
(C) 8 
(D) 9 
Trick:
Total = 7 + 5 = 12 
Each man will get = 12/3 = 4
Third man pay 24 Rs for 4 eggs
1 egg price = 6
Difference =  [(7-4)- (5-1)]*6 = 12
    2020-Jul-02
Ex: A shopkeeper bought 30 kg of rice at the rate of Rs.70 per kg and 20 kg of rice at the rate of Rs.70.75 per kg. If he mixed the both brand of rice and sold the mixture at Rs 80.50 per kg, what is his gain? 
(A) Rs. 210 
(B) Rs. 530 
(C) Rs. 470 
(D) Rs. 510
Trick:
Gain = (50 x 80.50) – (30 x 70 + 20 x 70.75)
= 4025 – (2100 + 1415)
= 4025 – 3515 => Rs. 510 
    2020-Jul-01
Ex: The speed of a motor boat is that of the current of water as 36:5. The boat goes along with the current in 5 hours 10 minutes. It will come back in:
(A) 5 hours 50 minutes 
(B) 6 hours
(C) 6 hours 50 minutes
(D) 12 hours 10 minutes
Trick:
Let the speed of motor boat be 36 km. /hr. and speed of current 5x km. /hr. 
Distance = 5 hours 10 minute × (36x + 5x)
= [(41x × 31)/ 6] km.
Rate of upstream = 36x – 5x = 31 x
Time taken = [{41x × (31/6)}/ (31x)] = 41/6 hours
= 6 hours 50 minutes
 
    2020-Jun-30
Ex: Akhil invested 10% more than Rahul. Rahul invested 10% less than Sunil. If the total sum of their investment is Rs. 5780. How much amount did Sunil invest?
(A) Rs. 2010
(B) Rs. 2000
(C) Rs. 2100
(D) Rs. 2210
Trick:
Let, Sunil's investment= Rs. 100
Rahul's investment= Rs. 90
Akhil's investment= Rs. 99 
Suneel's investment= Rs.= 100/289 *5780
Rs. 2000
    2020-Jun-29
Ex: The average age of A and B is 45 years. The ratio of their age is 2 : 1 respectively. What is the B's age?
(A) 20 years 
(B) 25 years 
(C) 30 years 
(D) 35 years 
Trick:
Sum of ratios = 2 + 1 = 3
Average age of the A and B = 45 
Sum of the ages of A and B = 90 years
3 = 90
1 = 30 years
So, B's age = 30 years
    2020-Jun-26
Ex: There are 2000 students in a school. Out of these 36% are girls. The monthly fee of each boy is Rs. 480 and monthly fee of each girls is 25% less than that of a boy. What is the total monthly fee of all students?
(A) 873600
(B) 742500
(C) 826400
(D) 924500
Trick:
Number of Girls = 720
Number of Boys = 1280
Total fee = 1280 × 480 + 720 × 360
= Rs. 873600
    2020-Jun-25
Ex: Annual incomes of A and B are in the ratio 3: 2, while the ratio of their expenditure is 5: 3. If at the end of the year each saves Rs. 1000, the annual income of A is -
(A) Rs. 9000
(B) Rs. 8000
(C) Rs. 7000
(D) Rs. 6000
Trick:
[{(3/5) x – 1000}/ {(2/5) x – 1000}] = 5/3
(3x – 5000) × 3 = (2x – 5000) × 5
9x – 15000 = 10x – 25000
x = 10000
Annual income of A = (3/5) ×10000 = Rs. 6000
    2020-Jun-24
Ex: Ganesh, Shankar and Sameer invested Rs. 4200, Rs. 8400 and 5400 respectively while starting a business. At the end of the year, they earned a profit of Rs. 24,000. Sameer invested 32% of .his share of the profit in a saving scheme. How much amount he is left with?
(A) 4280 Rs 
(B) 4652 Rs 
(C) 5520 Rs 
(D) 4896 Rs 
Trick:
Ratio of profit sharing=7 : 14 : 9
share of Sameer= 9 / 7+14+9 * 24000 = 7200
required answer=68% of 7200 = 4896
    2020-Jun-23
Ex: A car starts to running at the speed of 50 km./hr. After each half hour its speed increases by 10 km./hr. How much distance will be covered by it in 3 hours?
(A) 180 km. 
(B) 260 km. 
(C) 250 km. 
(D) 225 km.
Trick:
Distance = (50+60+70+80+90+100) × 1/2
= 225 km.
    2020-Jun-22
Ex: Two boats A and B start towards each other from two places, 150 km apart. Speed of the boats A and B in still water are 12 km/h and 18 km/h respectively. If A proceeds down and B up the stream, they will meet after how much time?
(A) 4.5 hours 
(B) 4 hours 
(C) 3 hours 
(D) 5 hours
Trick:
Let the speed of the stream be x kmph and both the boats meet after t hour.
(12+x) × t + (18-x) × t = 150
12t + 18t = 150
30t = 150
t = 5hrs