A percentage is simply a number shown “out of 100”. When your teacher says you scored 75%, it means you earned 75 out of every 100 marks. Percentages are used everywhere in Pakistan: board exam results, university admissions, discounts in bazaars, bank profits, and even mobile-load taxes. Once you understand one formula, all of these become easy.
The one formula you need
Percentage = (Part ÷ Whole) × 100
“Part” is the number you have; “Whole” is the total it is measured against.
Worked example 1 — exam marks
A student scores 823 marks out of 1100 in matric. Step by step:
- Part = 823, Whole = 1100.
- Divide: 823 ÷ 1100 = 0.7482.
- Multiply by 100: 0.7482 × 100 = 74.82%.
This is exactly how boards calculate your percentage, and why two students with the same marks in different total-marks schemes can have different percentages.
Worked example 2 — finding a percent of a number
A shop offers 15% off a shirt priced at Rs 2,400. How much do you save?
- Convert the percent to a fraction: 15% = 15 ÷ 100 = 0.15.
- Multiply by the price: 0.15 × 2,400 = Rs 360 saved.
- You pay 2,400 − 360 = Rs 2,040.
Worked example 3 — percentage increase
A bus fare rises from Rs 50 to Rs 65. The increase is:
- Change = 65 − 50 = 15.
- Divide by the old value: 15 ÷ 50 = 0.30.
- Multiply by 100 = 30% increase.
Common mistakes to avoid
- Using the wrong whole. For percentage change, always divide by the original (old) value, not the new one.
- Forgetting the × 100. 0.75 is a fraction; 75% is the percentage. They mean the same thing but are written differently.
- Adding percentages directly. A 10% discount followed by another 10% discount is not 20% off — the second discount applies to the already-reduced price.
Try it yourself
Use our free Percentage Calculator — it handles all four cases (percent of a number, what percent, increase/decrease, and exam marks with a grade guide) instantly, with no sign-up.