Quantitative Aptitude - Arithmetic Ability Questions

Given,Let the cost price of single book be Rs. 100.

The cost price of (9 + 1) = 10 pair i.e. 20 books = Rs. (100 × 20) = Rs. 2000.He gets profit of 26%.

So, the selling price of 9 pair i.e. 18 books = Rs. 2000 × (126/100) = Rs. 2520

Then,the selling price of single book = Rs. 2520/18 = Rs. 140

He gives 20% discount on the marked price of a book.

That means, when the selling price is Rs. 80 then the marked price is Rs. 100.

∴When the selling price of single book is Rs. 140, the marked price = Rs. 140 × (100/80) = Rs. 175

∴The percentage increase in marked price from the cost price = (175 –100)% = 75%

By investing Rs. 136, income obtained = Rs. 10.

By investing Rs. 6800, income obtained = Rs.1036×6800 = Rs. 500.

Ratio of investment of all the three members = (7 x 12) : (9 x 12) : (2/3 x 9 x 6)

= 7 : 9 : 3

Given Rushi's one year profit = Rs. 5600

=> Let the total profit = Rs. P

Then,

P x 7/19 = 5600

Total profit P = 19 x 5600/7 = Rs. 15,200.

Let the leak will empty the tank in x hrs 

Then, 1/9 - 1/x = 1/13

x = 29.25 hrs

The number of days required by a single kirlosker pump to fill the tank = 6 x 7 =42 days and the number of days required by a single USHA pump to fill the same tank = 2 x 18 =36 days.

Now , since efficiency is inversely proportional to the number of days. Hence,

Efficiency of one K - pumpEfficiency of U- pump=3642=67  

Let investment in each case be Rs. (143 x 117).

Income in 1st case = Rs.11143 x 143 x 117 = Rs. 1287.
Income in 2nd case = Rs.394×117 x 143 x 117= Rs. 1394.25

Clearly, 9 3/4% stock at 117 is better.