Hi Emily,

We have received this question before and it is confusing. "Exponential form" means involving exponents and there are many ways to write a number using exponents. For example $76385$ can be written as $76.385 \times 1000 = 76.385 \times 10^3.$ But $76385$ can also be written $763.85 \times 10^2.$ I think what is wanted is to write $461,885,811$ in "scientific notation". That means to place the decimal after the first digit and then multiply by the power of ten that will move the decimal to where it belongs. Hence if you write $4.61885811$ then the decimal has to move 8 places to the right to give you $461,885,811$ and hence $461,885,811$ written in scientific notation is $4.61885811 \times 10^8$.

Penny