Quantitative Aptitude - Arithmetic Ability Questions

The given number series 22, 26, 42, 78, 142, 244 follows a pattern that,

$$\begin{gathered} 22 \\ 22 + 22 = 22 + 4 = 26 \\ 26 + 42 = 26 + 16 = 42 \\ 42 + 62 = 42 + 36 = 78 \\ 78 + 82 = 78 + 64 = 142 \\ 142 + 102 = 142 + 100 = 242 \end{gathered}$$ 

Hence, the odd one in the given number series is 244.

Let 1 woman's 1 day work = x.

Then, 1 man's 1 day work = x/2 and 1 child's 1 day work  x/4.

So, (3x/2 + 4x + + 6x/4) = 1/7

28x/4 = 1/7 => x = 1/49

1 woman alone can complete the work in 49 days.

So, to complete the work in 7 days, number of women required = 49/7 = 7.

The given series follows a pattern that,

+4, +6, +8, +10, +12...

5

5 + 4 = 9

9 + 6 = 15

15 + 8 = 23

23 + 10 = 33

33 + 12 = 45

Hence, the missing number in the series is 33.

Number of liters of water in 125 liters of the mixture = 20% of 150 = 1/5 of 150 = 30 liters

Let us Assume that another 'P' liters of water are added to the mixture to make water 25% of the new mixture. So, the total amount of water becomes (30 + P) and the total volume of the mixture becomes (150 + P)

Thus, (30 + P) = 25% of (150 + P)

Solving, we get P = 10 liters