Quantitative Aptitude - Arithmetic Ability Questions

Given total students in the class = 60
Students who are taking Economics = 24 and
Students who are taking Calculus = 32
Students who are taking both subjects = 60-(24 + 32) = 60 - 56 = 4
Students who are taking calculus only = 32 - 4 = 28
probability that a randomly chosen student from this group is taking only the Calculus class = 28/60 = 7/15.

10% profit at half plot = 600000/2 x 10/100 = Rs. 30,000

15% profit at remaining half plot = 600000/2 x 15/100 = Rs. 45,000

Now, total profit = 30000 + 45000 = 75000

Profit % = 75000/600000 x 100 = 12.5 %

S.I. for 2 years = (514 - 415) = Rs. 99
S.I. for 1 year = 99/2

Principal = (415 - 99) = Rs. 316.

Let N be the required number. 

=> 60100x27x34xN=2664  

=> N = 2664x2x7x5/9  

=> N = 20720.

I=Prt

I=12

Balance = P +Prt

412

Find the balance at the end of the second year.

I = Prt=12.36

Balance =P + Prt

424.36

Let Mohan present age = p

ATQ,

5/6 x p = p - 5

p = 30

His wifes age = 30 - 3 = 27 yrs.

Watson bought the book for Rs. 240 and sold to Johny at a profit of 50%.

S.P = C.P(1 + P%/100)

=> S.P for Watson = C.P for Johny = 240(1 + 50/100) = 240 x 1.5 = Rs. 360

Let Johny quoted the marked price of the book as Rs. M

We know, SP = M.P(1 - Discount(%)/100)

Here discount = 10% to Shekar,

S.P for Johny = M(1 - 10/100) = 0.9M

But Johny want to earn 25% profit,

=> S.P = C.P(1 + P%/100)

=> 0.9M = 360(1 + 25/100)

=> M = (360x1.25)/0.9

=> M = Rs. 500

Therefore, Johny should quote Rs. 500 as the marked price of the book to get 25% profit and allowing 10% discount to Shekar.