Quantitative Aptitude - Arithmetic Ability Questions

Ratio of times taken by A and B = 1 : 2.

The time difference is (2 - 1) 1 day while B take 2 days and A takes 1 day.

If difference of time is 1 day, B takes 2 days.

If difference of time is 30 days, B takes 2 x 30 = 60 days.

So, A takes 30 days to do the work.

A's 1 day's work = 1/30

B's 1 day's work = 1/60

(A + B)'s 1 day's work = 1/30 + 1/60 = 1/20

A and B together can do the work in 20 days.

Given number series is 5  19  49  101  181  295 ?

Here the series follows pattern that

5   19   49   101   181   295  ?

  14   30   52    80     114   (difference)

      16  22   28     34 (difference)

         6     6     6  (Common difference)

Therefore, the missing number in the series is ? = 295 + 115 + 34 + 6 = 449.

In this type of problems the formulae is 5x-30×1211
x is replaced by the first interval of given time Here i.e 8
5*8-30*1211
= 12011min

Therefore the hands will be in the same straight line but not
together at 12011 min.past 8.

Here the given number series  3, 10.5, 36.75, 128.625, ? follows a pattern that

3

3 x 3.5 = 10.5

10.5 x 3.5 = 36.75

36.75 x 3.5 = 128.625

128.625 x 3.5 = 450.187

Hence the next number in the given number series is 450.187.

Let the quantity of alcohol and water be 4x litres and 3x litres respectively

4x/(3x+5) = 4/5 

20x = 4(3x+5)

8x = 20

x = 2.5

Quantity of alcohol = (4 x 2.5) litres = 10 litres.

Let the total number of children be x. 

Then, x * (20% of x) = 405  

=> x * 20x/100 = 405 

15x2 = 405 

=> x=45 

Number of sweets received by each child = 20% of 45 = 9.

Let the number be x, Then 

75% of x + 75 = x 

=> x - 75x/100 =75 

=> x =  300 .

Angle traced by the hour hand in 6 hours=(360/12)*6