Quantitative Aptitude - Arithmetic Ability Questions

Suppose B invested Rs. x for y months. Then, A invested Rs. 3x for 2y months.

So, A : B = (3x * 2y) : (x * y) = 6xy : xy = 6 : 1.

B's profit : Total profit  = 1 : 7.

Let the total profit be Rs. x Then,  1/7 = 4000/x  or x = 28000.

When R and W are the first and last letters of all the words then we can arrange them in 5!ways. Similarly When W and R are the first and last letters of the words then the remaining letters can be arrange in 5! ways.

Thus the total number of permutations = 2 x 5!  = 2 x 120 = 240

103.33 CP- 0.95 CP = 65

 CP = Rs. 780 

profit (%) = (936 - 780)/780  x 100 = 20%

Let sum = P and original rate = R. Then

[(P * (R+2) * 3)/100] - [ (P * R * 3)/100] = 360

3P*(R+2) - 3PR = 36000

3PR + 6P - 3PR = 36000

6P = 36000

P = 6000

Sum of the present ages of husband, wife and child = (23 * 2 + 5 * 2) + 1 = 57 years.

Required average = (57/3) = 19 years.

This can be easily simplified by Approximation process

Given 39.96% of 649.85 ÷13.07 = 45.14 - ? can be written as 

40% of 650 ÷13 = 45 - ?

$$\begin{gathered} 40 x 65010013 = 45 - ? \\ ? = 45 - 20 \\ ? = 25. \end{gathered}$$

Let sum = X. Then S.I = 16x/25

Let rate = R% and Time = R years.

Therefore,  (x * R * R)/100 = 16x/25   =>  R = 40/5 = 8

Therefore, Rate = 8% and Time = 8 years.