Profit is shared in the ratio of capital $\times$ time

How to use it

1. 1Break each partner's year into spells of constant capital and add $\text{capital}\times \text{months}$ across the spells.
2. 2Reduce the resulting weights to lowest terms before dividing the profit; the parts should then sum to a divisor of the profit.
3. 3If every partner invests for the same period, the time cancels and the split is by capital alone.

Step-by-step

1. 1
   $P:800\times 12=9600$; $Q:1200\times 4=4800$

   Why: Weight each capital by the number of months it was employed.

2. 2
   $9600:4800=2:1$, so Rs. $600$ splits into $3$ parts of Rs. $200$
3. 3
   $P$ receives $2\times 200=400$