A, B and C invest $5000, $4000 and $6000 respectively in a business. B gets 25% of the profit for managing the business and the remaining profit is divided amongst A, B and C in the proportion of their investments. If B gets $100 less than A and C together, what is the profit?
The Usual Method
Ratio of investments of A, B and C = 5 : 4 : 6. Let the profit be $‘x’.
Hence profit to be divided = x – 0.25x = 0.75x
Hence share of A =
Similarly, share of B =
And share of C =
Now since share of B = $100 less than A and C together,
Estimated Time to arrive at the answer = 75 seconds.
Note that the ratio of investments of A, B and C is 5 : 4 : 6. Hence they will get a total of 5x + 4x + 6x = 15x.
Now observe the options. Since B initially gets 25% of the profit, the remaining 75% is to be divided amongst A, B and C. This remaining 75% of the profit should be divisible by 15. (from 15x), so that the shares of A, B and C are whole numbers.
So for option ‘4’ => 1000 = 250 (25%) + 750 (75%).
Here the 75% i.e $750 is divisible by 15 and hence it is the answer.
(Note: We hit upon option ‘4’ straight as it is the easiest to break in 25% and 75%)
Estimated Time to arrive at the answer = 15 seconds.