Quantitative Aptitude - Arithmetic Ability Questions

5% of 40,000  = 5100 × 40,000 = 5 × 400 = 2,000  

Hence, 5% of 40,000 = 2,000.

16 of 225 is = 

$$\begin{gathered} 16 = p × 225100 \\ p = 1600225 = 7.1111 \end{gathered}$$

We Know that sum of the n natural numbers =n(n+1)2

Then sum of 50 natural numbers= 50(51)2= 1250

Average of the 50 natural numbers = 125050 = 25.5

Let the number of girls = x

=> x + x + 4 = 12

=> 2x = 8

=> x = 4

=> Number of girls = 4

=> Number of boys = 4 + 4 = 8

Volume of water displaced = (3 x 2 x 0.01) = 0.06 cu.m. 

Mass of man = Volume of water displaced x Density of water

 = (0.06 x 1000) kg

 = 60 kg.

Number of ways of selecting (3 consonants out of 7) and (2 vowels out of 4) =( C37×C24 ) = 210.

Number of groups, each having 3 consonants and 2 vowels =210

Each group contains 5 letters.

Number of ways of arranging 5 letters among themselves = 5! = 120. 

Required number of words = (210 x 120) = 25200.

By simplifying, we get 4/3