Quantitative Aptitude - Arithmetic Ability Questions

He can arrange his schedule in 8P6 = 20160 ways

P1+20100n > 2P 

Now, (6/5 x 6/5 x 6/5 x 6/5) > 2.

So, n = 4 years.

n (A) = (60/100 * 96) = 288/5, n (B) = (30/100 * 96) = 144/5, n (A ∩ B) = (15/100 * 96) = 72/5.

n(A ∪ B) = n (A) + n (B) - n (A ∩ B) = 72.

So, people who had either or both types of lunch = 72.

Hence, people who had neither type of lunch = (96 - 72)= 24.

Perimeter = Distance covered in 8 min. = (12000/60) * 8 = 1600m 

Let length = 3x metres and breadth = 2x metres.  

Then, 2(3x + 2x) = 1600 or x = 160.  

Length = 480 m and Breadth = 320 m.

Area = (480 x 320) = 153600 

Let the principle amount be Rs. P

Interest rate = 12%

Total amount he paid after 5 years = Rs. 1280

ATQ, 

$$\begin{gathered} P + I = PTR100 + P \\ 1280 = PTR100 + 1 \\ 1280 = P5 x 12100 + 1 \\ 16P10 = 1280 \\ P = 80 x 10 = 800 \end{gathered}$$

Hence, the amount he borrowed = P = Rs. 800.

The probability of an impossible event is 0.

The event is known ahead of time to be not possible, therefore by definition in mathematics, the probability is defined to be 0 which means it can never happen.

The probability of a certain event is 1.

In case B, odd times even will give even

Sum = [(S.I x T.D)/(S.I-T.D)] = (85 x 80)/(85-80) = Rs.1360