ExamShortcut

Ratio, Proportion, Partnership & Ages

πŸ”’ Log in to track
high importance~2 Q in Tier 123 formulas⚑ 15 shortcuts5 subtopics

Ratio technique with its three biggest exam containers: proportion (mean/third/fourth proportional), partnership (capital Γ— time profit splits) and ages (present vs shifted ratios). Tier 1 reliably has 2 questions from this cluster; most are 30–45 second marks once the multiplier habit is built.

Track record in the exam

avg 1.0 Q / shift2024: 0–2 Q2025: 1 Q

Questions per shift in recent SSC CGL papers.

Test difficulty mix (63 questions)

17 easy32 medium14 hard

Question patterns exams keep repeating

Taken from previous-year papers. If a pattern is marked "very common", expect to see it in your exam.

Share money in a ratio

very common

"β‚Ή2,500 is divided among A, B and C in the ratio 2 : 3 : 5."

Add the ratio numbers to get the total parts.

Find one part, then multiply.

Example

β‚Ή2,500 is divided among A, B and C in the ratio 2 : 3 : 5. Largest share?

Total parts = 2 + 3 + 5 = 10

1 part = 2500 Γ· 10 = 250

Largest = 5 parts = 5 Γ— 250 = β‚Ή1,250

Learn this in β€œRatio basics & dividing amounts” β†’

Join two ratios into one

very common

"A : B = 2 : 5 and B : C = 6 : 7. Find A : B : C."

Make the common letter the same number in both ratios.

Then write all three together.

Example

If A : B = 2 : 5 and B : C = 6 : 7, find A : B : C.

B is 5 in one ratio and 6 in the other; make both 30

A : B = 2 : 5 = 12 : 30 (Γ— 6)

B : C = 6 : 7 = 30 : 35 (Γ— 5)

A : B : C = 12 : 30 : 35

Learn this in β€œRatio basics & dividing amounts” β†’

Third, fourth and mean proportional

common

"Find the third proportional to 12 and 18."

Write the proportion with an unknown x.

Cross-multiply and divide.

Example

Find the third proportional to 12 and 18.

Third proportional means 12 : 18 = 18 : x

12 Γ— x = 18 Γ— 18 = 324

x = 324 Γ· 12 = 27

Learn this in β€œProportion & proportional division of terms” β†’

Share profit between partners

very common

"A invests β‚Ή30,000 for 12 months and B β‚Ή40,000 for 6 months. Find A's share of the profit."

Multiply each person's money by the months it stayed.

Share the profit in that ratio.

Example

A invests β‚Ή30,000 for 12 months, B invests β‚Ή40,000 for 6 months. Profit is β‚Ή28,800. A's share?

A: 30,000 Γ— 12 = 360,000

B: 40,000 Γ— 6 = 240,000

Ratio = 3 : 2

A's share = 3/5 Γ— 28,800 = β‚Ή17,280

Learn this in β€œPartnership” β†’

Ages in a ratio

very common

"Present ages are in the ratio 4 : 5. After 16 years it is 6 : 7."

Write the ages as 4x and 5x.

Add (or subtract) the years to both, then cross-multiply.

Example

Ages are in the ratio 4 : 5. After 16 years the ratio is 6 : 7. Sum of present ages?

Ages = 4x and 5x

After 16 years: (4x + 16) : (5x + 16) = 6 : 7

Cross-multiply: 28x + 112 = 30x + 96, so x = 8

Ages are 32 and 40, sum = 72 years

Learn this in β€œProblems on ages” β†’

Income, spending and savings in a ratio

common

"Incomes are 8 : 5, spendings 5 : 3, and each saves β‚Ή1,200."

Write income and spending with separate letters (x and y).

Savings = income βˆ’ spending, and both savings are equal.

Example

Incomes of A and B are 8 : 5, spendings are 5 : 3, and each saves β‚Ή1,200. Find A's income.

Incomes 8x and 5x, spendings 5y and 3y

Equal savings: 8x βˆ’ 5y = 5x βˆ’ 3y, so 3x = 2y, y = 1.5x

A saves 8x βˆ’ 7.5x = 0.5x = 1200, so x = 2400

A's income = 8 Γ— 2400 = β‚Ή19,200

Learn this in β€œMoney ratios: income–expenditure, coins & mixed amounts” β†’

Coins in a ratio

occasional

"Coins of 50 paise, 25 paise and 10 paise are in the ratio 7 : 6 : 5 with total β‚Ή550."

Find the value of one set of coins (7 + 6 + 5 coins).

Divide the total by it to get the number of sets.

Example

50p, 25p and 10p coins are in the ratio 7 : 6 : 5 and total β‚Ή550. How many 25p coins?

One set: 7Γ—50 + 6Γ—25 + 5Γ—10 = 550 paise

Total = β‚Ή550 = 55,000 paise

Sets = 55,000 Γ· 550 = 100

25p coins = 6 Γ— 100 = 600

Learn this in β€œMoney ratios: income–expenditure, coins & mixed amounts” β†’

Ratio of (x + y) to (x βˆ’ y)

occasional

"If (x + y) : (x βˆ’ y) = 5 : 3, find x : y."

Give the two sides a common multiplier k.

Add them to get x, subtract them to get y.

Example

If (x + y) : (x βˆ’ y) = 5 : 3, find x : y.

Let x + y = 5k and x βˆ’ y = 3k

Add: 2x = 8k. Subtract: 2y = 2k

x : y = 8 : 2

x : y = 4 : 1

Learn this in β€œProportion & proportional division of terms” β†’

Your next step

New here? Start with subtopic 1 in Learn. Revision mode? Jump straight to the test and let it tell you what to fix.