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The 35% Method (Non-Round Percentages)

Break non-round percentages into easy chunks.

When to use

Calculating 15%, 35%, 45%, 55%, 65%, 85%, 95% of a number.

Steps

  1. 1.Break the percentage into round parts
  2. 2.35% = 30% + 5% = 3 x 10% + half of 10%
  3. 3.Calculate each part and add

Example: 35% of 240

10% of 240 = 24

30% = 3 x 24 = 72

5% = half of 24 = 12

35% = 72 + 12 = 84

Mental approach

Find 10% first, then build up. 35% = 3.5 x 10%, or 30% + 5%.

Pen & paper approach

Write 10% and 5% on the side, then combine as needed.

Tips

  • •Always start with 10% — it's your building block
  • •5% is always half of 10%
  • •15% = 10% + 5%, 45% = 50% - 5%

Try it yourself

15% of 600

45% of 200

85% of 400