Step 1: Move the decimal point from its current position (the black dot) to a position immediately to the right of the first nonzero digit (the red dot).
7.14285.714286
Step 2: We moved the decimal point 5 spaces to the right. Therefore, the exponent on base 10 will be positive 5.Now we know that the:
Mantissa = 7.14285714286
Exponent = 5
So, the solution is:
$$714285.714286 = \color{blue}{ 7.14285714286} \cdot 10^{ \color{red}{ 5 }}$$