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Growth Multipliers

Multiply by 1.x by splitting into base + growth percentage.

When to use

Problems like '1,000,000 x 1.15' (15% growth).

Steps

  1. 1.Recognize that x1.15 means +15% growth
  2. 2.Keep the base (x1 = original amount)
  3. 3.Calculate the growth part (0.15 x base)
  4. 4.Add them together

Example: 1,000,000 x 1.15

1.15 = 1 + 0.15

Base: 1,000,000

15% of 1,000,000 = 150,000

Total: 1,000,000 + 150,000 = 1,150,000

Mental approach

1,000,000 x 1.15: base is 1M, growth is 15% of 1M = 150K, total = 1,150,000.

Pen & paper approach

Write: base + (growth % x base) = answer.

Tips

  • •x1.5 = number + half of itself
  • •x1.25 = number + quarter of itself
  • •x1.1 = number + 10% (just add a zero-shifted version)
  • •x1.05 = number + 5% (half of 10%)

Try it yourself

2,000,000 x 1.2

500,000 x 1.5

4,000,000 x 1.05