The goal of writing a number in scientific notation is to have a decimal number, with one digit to the left of the decimal point, followed by a ×10 to some power. To format the number this way, multiply the 0.0003 by 10−by the power of 4 times, making it 3. Each multiplication by 10 moves the decimal point one digit to the left, but in order to keep the same number, multiply 3 by 10−by the power of 4.