Multiplying in scientific notation

The question

(1.2 × 10⁻³) × (8 × 10²)

(1.2 × 10⁻³) × (8 × 10²)

(1.2 × 10⁻³) × (8 × 10²)
1.2×8=9.6
−3+2=−1
9.6 × 10⁻¹
1 ≤ 9.6 < 10
(1.2 × 10⁻³) × (8 × 10²)=9.6 × 10⁻¹
  1. Handle the two parts separately: the coefficients multiply and the powers add.
  2. Multiply the coefficients: 1.2 × 8 = 9.6.
  3. Now the powers. Multiplying powers of the same base adds the exponents: −3 + 2 = −1. So the powers give 10⁻¹.
  4. Put them together: 9.6 × 10⁻¹. Check it: a coefficient has to be at least 1 and less than 10, and 9.6 is.
  5. So the answer is 9.6 × 10⁻¹ — 1.2 × 8 = 9.6 and the powers give 10⁻¹.

How it works.

  1. 01

    Handle the two parts separately: the coefficients multiply and the powers add.

  2. 02

    Multiply the coefficients: 1.2 × 8 = 9.6.

  3. 03

    Now the powers. Multiplying powers of the same base adds the exponents: −3 + 2 = −1. So the powers give 10⁻¹.

  4. 04

    Put them together: 9.6 × 10⁻¹. Check it: a coefficient has to be at least 1 and less than 10, and 9.6 is.

  5. 05

    So the answer is 9.6 × 10⁻¹ — 1.2 × 8 = 9.6 and the powers give 10⁻¹.