Quantitative Aptitude - Arithmetic Ability Questions

The given series 

12   24   26.5   79.5   ?   330 follows a pattern that,

12 x 2 = 24

24 + 2.5 = 26.5

26.5 x 3 = 79.5

79.5 + 3 = 82.5

82.5 x 4 = 330

Hence, the missing number is 82.5

Let the required number of days be x.

Less persons, More days (Indirect Proportion)

More working hours per day, Less days (Indirect Proportion)

Persons30:39Working hours/day6:5⋮⋮ 12:x

=> 30 * 6 * x = 39 * 5 * 12 

=> x= 13

Required number = H.C.F. of (1657 - 6) and (2037 - 5)

= H.C.F. of 1651 and 2032 = 127.

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.

When the hands of the clock are in the same straight line but not together, they are 30 minute spaces apart.
At 7 o'clock, they are 25 min. spaces apart.
Minute hand will have to gain only 5 min. spaces.
55 min. spaces are gained in 60 min.

5 min spaces are gained in 6055*5 min  = 5511min 

so, Required time = 5511 min  past 7

We shall find the day on 1st April, 2001.

1st April, 2001 = (2000 years + Period from 1.1.2001 to 1.4.2001)

Odd days in 1600 years = 0

Odd days in 400 years = 0

Jan. Feb. March April

(31 + 28 + 31 + 1) = 91 days 0 odd days.

Total number of odd days = (0 + 0 + 0) = 0

On 1st April, 2001 it was Sunday.

In April, 2001 Wednesday falls on 4th, 11th, 18th and 25th.

The given number series 410, 409, 413, 404, ? , follows a pattern that 

410

$$\begin{gathered} 410 - 13 = 409 \\ 409 + 22 = 413 \\ 413 - 33 = 404 \\ 404 + 42 = 420 \end{gathered}$$

Hence, the next number in the given series is 420.