Mixed Quantitative Aptitude Questions Set 172

1. There are 3 members in a family – husband, mate and their daughter. Husband’s age is thrice his daughter’s age and mate is 3 years younger than his husband. what's the individual ratio of ages of daughter, husband and mate if their average age is 70?
   30: 90:87
   20:34:90
   10:40:90
   35:45:80
   15|:25:65
   Option A
   Let daughter’s age = x
   Husband’s age = 3x
   mate’s age = 3x – 3
   ⇒ x + 3x + (3x – 3) = 70 × 3
   ⇒ 7x =210
   ⇒ X = 30
   Daughter’s age = 30 years
   Husband’s age = 30 × 3 = 90 years
   mate age = 30 × 3 – 3 = 87 years
   Required ratio = 30 : 90 : 87
   
   
    



2. A spherical tank of surface area 616 sq m crammed with water planned to hide with a lid of the biggest circle size lying on the tank . Then what's the diameter of the circular lid?
   12
   16
   14
   15
   11
   Option C
   Surface area of spherical vessel = 616 cm2
   ∴ 4πr2 = 616
   r2 = 616/ 4π =49
   
   ⇒ r = 7 cm
   ∴ Diameter of the lid of largest circle lying on vessel = 2r = 2 × 7 = 14 cm
   
   
    



3. If the average of six numbers is 30 and the average of first three numbers is 20 and the last two number is 19,What is the fourth number from the starting?
   23
   78
   87
   82
   90
   Option D
   Let the five numbers be a, b, c, d, e, f
   Given (a + b + c) / 3 = 20
    a+ b + c = 60
   (e + f)/2 = 19
    e+ f = 38
   a+ b+ c + d + e +f = 30 X 6 = 180
   60 + d + 38 = 180
    d = 180 – 60 – 38 = 82
   so the fourth number is 82.
   
   
    



4. Three students on their flash lights and turn off after every 12sec, 15sec , 20 sec respectively. If they all turn off simultaneously at 09:00: 00 hrs. If they continue this play then at what time they are expected to turn off their lights?
   8.25
   9.01
   8.09
   9.04
   8.00
   Option B
   Interval of change the light = l c m ( 12 , 15 , 20 )
   = 60 sec = 1 min
   Hence next at 9: 01 :00 they will turn off the light simultaneously.
   
   
    



5. In a population 20% of women are 200 less than three fifth of the total women population .Then how many number of women are there?
   500
   400
   200
   600
   700
   Option A
   Let the population of the women be x.
   Then (3/5) x - 200 = ( 20% of x )
   3 x/5 – ( 20 x / 100 ) = 200
   x = 500
   
   
    



6. A father decided to give his retirement amount Rs. 7,40,000 to his sons A, B , C in the proportion 1/3 : 2/ 5 : 3/6. Then what is the average amount of first two sons got from their father?
   1,20,00
   2,00,000
   2,20,000
   3,00,000
   4,00,000
   Option C
   Given proportion = 1/3 : 2/5 : 3 /6 = 10 : 12 : 15
   A ‘s share = (10/ 37 ) x 7,40,000 = Rs. 2,00,000
   B’ s share = (12 / 37) x 7, 40 , 000 = Rs. 2, 40, 000
   Hence average =( 200000 + 240000 )/ 2 = Rs. 2, 20 , 000.
   
   
    



7. Three years back the age of brother and sister was 5: 6 respectively. Five years after the ratio of their age become 7 :8 .Then what is the age of the brother ?
   10
   20
   30
   15
   25
   Option B
   Let the brother age be 5x and the sister age be 6x.
   Five years after brother age 5x + 3 + 5 = 5x + 8
   Five years after sister age 6x + 3+ 5 = 6x + 8
   So 5x + 8 / 6x + 8 = 7 / 8
    8 ( 5x + 8) = 7 ( 6x + 8)
    X =4 yrs
   Age of the brother is = 5 x 4 = 20 years
   
   
    



8. Two friends planned to buy a land into a partnership. Friend A invests Rs 45,000 and friend B invests Rs. 20,000. After 6 months Friend C has joined with and ready to give certain amount . If the car company gave the total discount Rs 20,000 and so Friend B got Rs.2000 back. Then What is the investment of Friend C?
   16,20,000
   15,90,000
   14,35,000
   13,90,000
   17,90,000
   Option A
   Let the investment of Friend A, B, C be x, y , z.
   The discount ratio is d1,d2,d3.
   x : y: z = 45,000 x 12 : 20,000x12 : z = 5,40,000 : 2,40,000 :z ( 12 months)
   total investment : B investment :: total discount : B discount
   7,80,000 + z : 2,40,000 :: 20,000: 2000
   So , 2,40,000/ ( 7,80,000 + z) = 2000 / 20000
   =>z=16,20,000
   
   
    



9. Three boats travelling at 10 km /h , 15 km/h and 20 km/h respectively in still water And they travel face to face directly to each other. At present they are 50 km apart. How many kilometers are they one minute before they clash each other?
   3.8
   4.8
   5.9
   5.8
   6.5
   Option C
   One minute before clash distance = Total – ( total distance of three boats before a minute)
   = 50 – ( 10 x 59 /60 - 15 x 59 /60 – 20 x 59 /60)
   = 50 – ( 9.8 + 14.6 + 19.7 )
   = 5.9 km
   
   
    



10. Vinay wants to travel from Delhi to Banglore which is 600 kilometer. If he opt for train , it takes 12 hrs more than the flight. If the speed of the train is doubled ,it takes ten hours less than the flight. what's the speed of the flight?
    300
    200
    400
    250
    342
    Option A
    Speed of the train = 600 / 12 = 50 km / hr
    If it speed doubled = 50 x 2 = 100 km/hr
    So 100 / 10 = 10 times increased.
    Then original time 12-10 = 2 hrs
    Therefore speed = 600 / 2 = 300 kmph .