Mixed Quantitative Aptitude Questions Set 21

Quantitative Aptitude Questions Bank PO Tricks for SBI PO, IBPS PO, NIACL, NICl, BoB, Dena Bank PGDBF and other competitive exams

1. If 75 is added to 75% of a number then the number becomes 125% of it. Find the original number.
   A) 187.5
   B) 150
   C) 200
   D) 112.5
   E) 165.5
   
   View Answer

     Option B
   Solution:
   75% = 3/4, 125% = 5/4
   We have to make 3/4 to 5/4
   3 => 5 means increase of 2
   So 2 = 75 (the number that is to be added
   And 4 (denominator – the original number)  = 75/2 * 4 = 150
2. After a discount of 11.11%, a trader still makes a gain of 14.28%. At how much percent above the cost price does he mark his goods?
   A) 16.67%
   B) 23.37%
   C) 22.22%
   D) 28.56%
   E) 31.22%
   
   View Answer

     Option D
   Solution:
   Discount is calculated on MP
   11.11% = 1/9  (1 – discount, 9 – MP)
   MP – Discount = SP
   So 9 – 1 = 8
   Profit% = 14.28% = 1/7 (1 – gain, 7 – CP)
   SP = CP + Profit
   So SP = 7 + 1 = 8
   Both SP are found to be same
   So CP : SP : MP = 7 : 8 : 9
   Required % = (9-7)/7 * 100 = 200/7%
3. A water tank has three taps A, B, and C. A fills four buckets in 24 mins, B fills 8 buckets in 1 hour and C fills 2 buckets in 20 minutes. If all the taps are opened together a full tank is emptied in 2 hours. If a bucket can hold 5 litres of water, what is the capacity of the tank?
   A) 240 l
   B) 280 l
   C) 200 l
   D) 300 l
   E) 250 l
   
   View Answer

     Option A
   Solution:
   Bucket is to be emptied in 2 hours or 120 minutes
   In 24 mins, A can fill 4 buckets
   So in 120 minutes, it can fill 20 buckets
   Similarly
   In 120 minutes, B can fill 16 buckets
   In 120 minutes, C can fill 12 buckets
   Total = 20+16+12 = 48
   1 bucket = 5 litre
   So 48 buckets = 240 litres
4. 7 men, 5 women and 8 children together have to distribute 1740 books in a total 3 days. On the first day all distribute books. On second day 2 women and 3 children were absent and on the third day 3 men and 5 children were absent. If the ratio of the number of books distributed in a day by a man, a woman and a child was 5 : 4 : 2 respectively, a total of approximately how many books were distributed on the second day?
   A) 650
   B) 700
   C) 510
   D) 600
   E) 570
   
   View Answer

     Option E
   Solution:
   The ratio 5 : 4: 2 specifies the efficiency
   In 3 days, total men = 7 + 7 + 4 = 18
   In 3 days, total women = 5 + 3 + 5 = 13
   In 3 days, total children = 8 + 5 + 3 = 16
   So 18*5x + 13*4x + 16*2x = 1740
   Solve, x = 10
   So second day distribution:
   7*5x + 3*4x + 5*2x = 57x = 57*10 = 570  
5. Keshav invests some amount. It amounts to Rs 6000 in 2 years and to Rs 8000 in 4 years if compounded annually. Fin the sum invested by him.
   A) Rs 4000
   B) Rs 5400
   C) Rs 5000
   D) Rs 4500
   E) Rs 4800
   
   View Answer

     Option D
   Solution:
   When difference of year is same in CI (like here 2 years and then 2+2 = 4 years):
   x(principal) : 6000 = 6000 : 8000
   Solve, x = Rs 4500
6. The price of an article is first increased by 25%, then by 10% and at last increased by 14 2/7%. If the original price was Rs 140, find the new price after 3 increments.
   A) 180
   B) 160
   C) 200
   D) 230
   E) None of these
   
   View Answer

     Option E
   Solution:
   25% = 1/4
   10% = 1/10
   14 2/7% = 1/7
   Original price = 140
   After first increment = 140 + 1/4 * 140 = 175
   After second increment = 175 + 1/10 * 175 = 192.5
   After third increment = 192.5 + 1/7 * 192.5 = Rs 220  
7. A shopkeeper bought an article for Rs 12000. He marked the price 25% above the cost price. If during selling a discount of 10% is given on the marked price, find the profit/loss% incurred by the shopkeeper.
   A) 15%
   B) 12.5%
   C) 12%
   D) 10%
   E) 14.5%
   
   View Answer

    Option B
   Solution:
   MP is 25% above CP
   25% = 1/4 (1 – increased price, 4 – CP)
   So MP = CP + increased price = 4(CP) + 1 = 5(MP)  ……..(i)
   Discount = 10% = 1/10
   So SP = 10(MP)  – 1 = 9(SP)  …….(ii)
   Now make MP same in both equations by multiplying equation(i) by 2
   So 8(CP) + 2 = 10 (MP)
   So
   CP : MP : SP = 8 : 10 : 9
   So profit% = (9-8)/8 * 100 = 12.5%
   
8. A solution of sugar syrup has 35% of sugar. Another solution has 20% sugar. How many litres of the second solution must be added to 40 litres of the first solution to make a solution of 25% sugar?
   A) 40 l
   B) 60 l
   C) 80 l
   D) 70 l
   E) 50 l
   
   View Answer

     Option C
   Solution:
   35% of 40 + 20% of x = 25% of (40+x)   
9. Train A crosses a pole and a platform in 18 seconds and 39 seconds respectively. The length of the platform is 157.5 m. What will be the length of train B if it is equal to the sum of half of the length of train A and twice the length of the platform?
   A) 328.5 m
   B) 382.5 m
   C) 238.5 m
   D) 315 m
   E) None of these
   
   View Answer

    Option B
   Solution:
   (l+ 157.5)/s =  39
   Also l/s = 18
   Solve both, l = length of train = 135m
   So length of train B = (135/2) + 2 * 157.5 = 382.5 m
10. A plane left 30 minutes later than the scheduled time and in order to reach its destination 1500 km away in time, it had to increase its speed by 250km/hr from its usual speed. Find its usual speed.
    A) 720 km/hr
    B) 750 km/hr
    C) 790 km/hr
    D) 840 km/hr
    E) None of these
    
    View Answer

     Option B
    Solution:
    Solve with options:
    Take 750. It cancels out 1500, so 1500/750 = 2 hours
    it left 30 minutes later, so it has to cover distance in 2 – 1/2 = 1 hour 30 minutes  = 3/2 hours
    then speed should be 1500/(3/2) = 1000 km/hr
    Speed is increased by 250 km/hr
    And 750 + (250) = 1000 – satisfies the condition.