12500 shares, of par value $ 20 each, are purchased from Ram by Mohan at a price of $ 25 each. Find out the amount required to purchase the shares. If Mohan further sells the shares at a premium of $ 11 each, then find out his gain in the transaction.

Given that, 30 % of A = 20 % of B
? A/B = 20/30 = 2/3
? A : B = 2 : 3

Let initial quantity be Q, and final quantity be F

F = Q(1 - 8/Q) 4

=> Q = 20

? log₅[(x² + x ) / x] = 2
? log₁₀(x + 1) = 2
? x + 1 = 25
? x = 24

∴ Sum of 20 numbers (0 x 20) = 0.

It is quite possible that 19 of these numbers may be positive and if their sum is a then 20th number is (-a).

We know that speed is inversely proportional to time.
Given that, (Speed of A ) : (speed of B ) = 2 : 7
?(Time taken by A ) : (Time taken by B ) = 1/2 : 1/7 = 7 : 2

Let th distance = D
and usual speed = V
According to the question,
D/(3V/4) - D/V = 2
? D/V = 3 x 2 = 6
Time taken to cover the distance with usual speed = 6 h

?2ⁿ = 64
? 2^n/2 = 2⁶
? n/2 = 6
? n = 12

Distance = 160 km
Relative Speed = 8 + 2 = 10
Time = Distance/Relative speed = 160/10 = 16 h