Step 1: Write both numbers in scientific notation. For more information, use the SN Converter.
$$ 3\cdot 10^{2} = 3\cdot 10^{2} $$$$ 1.3\cdot 10^{6} = 1.3\cdot 10^{6} $$Step 2: Multiply the numeric parts. Note that in intermediate calculations, we need 6 significant digits.
$$ 3 \cdot 1.3 \approx 3.9 $$Step 3: Multiply $10^{ 2 }$ by $10^{ 6 }$:
$$ 10^{ 2 } \cdot 10^{ 6 } = 10^{ 2+6 } = 10^{ 8 } $$Step 4: Write the solution as the product of the numbers obtained in steps two and three.
$$ 3.9 \cdot 10^{ 8 } $$