Lessons / Quantitative aptitude
Quantitative aptitude · Day 3

Partnership

Profit is split by capital × time, never by capital alone. Rupee-months is the only number that matters.

Why this topic matters

Two friends start a shop. One puts in Rs 30,000, the other Rs 20,000. If the shop earns Rs 10,000, it is fair to split it 3 : 2. Partnership is just that fairness rule.

Partnership is ratio with one extra idea: money that stays in the business longer counts for more. Profit is shared in the ratio of (money × time).

Profit share = capital × time

If everyone invests for the same time, share profit in the ratio of the money invested.

If the times differ, multiply each person's money by the number of months it stayed in. Rs 10,000 for 12 months counts the same as Rs 20,000 for 6 months.

A sleeping partner only invests; a working partner also runs the business and may get a salary or a fixed % of profit first. Take that out before splitting the rest.

A30,000 x 12B20,000 x 12
Same time: profit 3 : 2
Share ratio = C1 × T1 : C2 × T2 : ...
Capital times months.
Working partner: salary first, then split the rest
Read carefully what is paid before the split.
Example 1A invests Rs 40,000 for a year. B joins after 4 months with Rs 60,000. The year's profit is Rs 34,000. B's share?
  1. A: 40,000 × 12 = 4,80,000. B: 60,000 × 8 = 4,80,000.B's money was in for 12 - 4 = 8 months.
  2. Ratio 1 : 1.Equal capital-months.
  3. B gets 17,000.
Example 2A and B start with Rs 50,000 and Rs 30,000. After 6 months A withdraws Rs 20,000. Profit at year end is Rs 23,000. Find A's share.
  1. A: 50,000 × 6 + 30,000 × 6 = 4,80,000.Split A's year into the two periods with different amounts.
  2. B: 30,000 × 12 = 3,60,000.
  3. Ratio 480 : 360 = 4 : 3.Divide by 1,20,000.
  4. A = 4/7 × 23,000 = 13,142.86.

Formula summary

Share ratio
C1 × T1 : C2 × T2 : ...
Joins late / leaves early
Count only the months that money was actually in.
Withdraw or add mid-year
Split that partner into two blocks: (old capital × months) + (new capital × months).
Working partner
Take out the salary / commission first, split the rest by capital ratio.
Given profit ratio and time ratio
Capital ratio = profit / time for each.

Shortcuts and tricks

Rupee-months table

Use it when: Any partnership with changes.

  1. One row per partner, sum of capital × months.
  2. Reduce the totals to a ratio before dividing profit.
ExampleA: 40,000 all year but withdraws 10,000 after 6 months. B: 60,000 all year. Profit 38,000. A's share?
  1. A = 40k × 6 + 30k × 6 = 4.2 lakh. B = 7.2 lakh.
  2. 7 : 12, 19 parts of 2000.
  3. A = 14,000.

Common mistakes

Using the money ratio when the partners were in for different months.
Multiply each amount by its months.

Before you move on, you should be able to...

  • share profit in the ratio of capital × months
  • handle a partner joining late or withdrawing money midway
  • take out a working partner's salary first

Practice questions (7)

Try each one before opening the solution. Or practise them one by one so your score is saved.

easy A invests Rs 20,000 for the year. B invests Rs 30,000 after 4 months. Profit Rs 18,000. B's share?
  1. A = 20k × 12 = 2.4 L. B = 30k × 8 = 2.4 L.
  2. 1:1.

Answer: Rs 9,000

medium A is a working partner getting 10% of profit as salary; the rest is split 3:2 (A:B). Profit Rs 50,000. A's total?
  1. Salary 5000.
  2. 45000 × 3/5 = 27000.
  3. Total 32000.

Answer: Rs 32,000

medium A starts with Rs 3,500. After 5 months B joins. Profit is split 2:3 at the year end. B's capital?
  1. 3500 × 12 : B × 7 = 2 : 3.
  2. B = 3500 × 12 × 3 / (7 × 2) = 9000.

Answer: Rs 9,000

hard A, B, C invest 5,000, 6,000, 8,000 for 12, 10, 6 months. Profit Rs 7,000. C's share?
  1. Rupee-months (thousands): 60, 60, 48 → 5 : 5 : 4.
  2. 14 parts of 500.
  3. C = 4 × 500.

Answer: Rs 2,000

hard Profit ratio of A, B, C is 5:7:8 and their time ratio is 3:4:5. Capital ratio?
  1. 5/3 : 7/4 : 8/5, x60.

Answer: 100:105:96

hard A invests 3 times B, and B invests 2/3 of what C invests. Profit Rs 6,600. B's share?
  1. A = 3B, C = 1.5B → 3 : 1 : 1.5 = 6 : 2 : 3.
  2. 11 parts of 600.

Answer: Rs 1,200

hard A and B invest in 3:5. After 4 months A withdraws half his capital. Year-end profit Rs 5,600. A's share?
  1. A = 3 × 4 + 1.5 × 8 = 24. B = 5 × 12 = 60.
  2. 24 : 60 = 2 : 5.
  3. 2/7 of 5600.

Answer: Rs 1,600

Class plan (2 hours, for trainers)

A tested order for teaching this topic in one 2-hour session. Present mode follows the same order.

10 minWarm-up.
25 minEqual time: profit in the money ratio.
30 minDifferent times; joining and leaving.
15 minAdding or withdrawing midway.
10 minWorking partner salary.
25 minPractice set.
5 minRecap.