4e-10 = -6
4E10 typically refers to a numerical representation in scientific notation, meaning 4 x 10^10. This indicates the number 40,000,000,000. It is often used in scientific and engineering contexts to express very large numbers more compactly.
The E on a calculator means "times ten to the power of." 4E10 means 4 times 10 to the power of 10.
To add (4 \times 10^{10}) and (2 \times 10^{12}), it's helpful to express them with the same exponent. Converting (2 \times 10^{12}) to the same exponent as (4 \times 10^{10}) gives (200 \times 10^{10}). Now, adding them together results in (4 \times 10^{10} + 200 \times 10^{10} = 204 \times 10^{10}), which can also be expressed as (2.04 \times 10^{12}).