0.0009 in Scientific Notation

0.0009 in scientific notation

0.0009 = 9 \times 10^{-4}

0.0009 in scientific notation is 9 × 10⁻⁴ – the decimal point moves 4 places to the right, so the power of ten is −4.

  • E-notation: 9E-4 (calculators, Excel, programming)
  • Engineering notation: 900 × 10⁻⁶ (the power is a multiple of 3)
  • Said aloud: nine times ten to the power of negative four
  • Significant figures: 1
  • Order of magnitude: \displaystyle 10^{-4}
  • As a fraction: 9/10,000

Step-by-step solution

The problem

\text{Write } 0.0009 \text{ in scientific notation}
1

Find the coefficient

a = 9

Scientific notation is \displaystyle a \times 10^{n} with \displaystyle 1 \le a < 10. Put the decimal point just after the first non-zero digit (9).

2

Count the places the decimal point moves

  1. 0.0009
  2. 0.009
  3. 0.09
  4. 0.9
  5. 9

From \displaystyle 0.0009 to \displaystyle 9 the decimal point moves 4 places to the right.

3

Choose the sign of the exponent

n = -4

The number is less than 1, so the point moved right and the exponent is negative: each place right multiplies by 10, and \displaystyle 10^{-4} divides it back.

4

Write it in scientific notation

0.0009 = \textcolor{#0b5c56}{9 \times 10^{-4}}

Check

9 \times 10^{-4} = 9 \div 10{,}000 = 0.0009 \;\checkmark

Multiply the coefficient by the power of ten (a negative power divides) to get back the number.

The digits 9 at other powers of ten

Only the power changes when the decimal point moves – each place right is one more step of ten.

NumberScientific notationE-notation
0.99 × 10⁻¹9E-1
0.099 × 10⁻²9E-2
0.0099 × 10⁻³9E-3
0.00099 × 10⁻⁴9E-4
0.000099 × 10⁻⁵9E-5
0.0000099 × 10⁻⁶9E-6
0.00000099 × 10⁻⁷9E-7
0.000000099 × 10⁻⁸9E-8
0.0000000099 × 10⁻⁹9E-9

Other numbers × 10⁻⁴

Try different values

Frequently asked questions

Is 90 × 10⁻⁵ the same as 9 × 10⁻⁴?

It has the same value, but it isn’t scientific notation: the number in front must be at least 1 and less than 10, and 90 is not. Move the point one more place and add 1 to the power: 9 × 10⁻⁴.

Any other number – or multiplying, dividing, adding and subtracting in scientific notation – use the Scientific Notation Calculator.