To find the half-life of uranium-238, we can add the half-life of uranium-235 to the additional duration given.
The half-life of uranium-235 is 700,000,000 years, or in decimal form:
\[ 700,000,000 \text{ years} = 7.0 \times 10^8 \text{ years} \]
The half-life of uranium-238 is given as:
\[ 4.463 \times 10^{11} \text{ years} \]
Now, we can convert this to decimal form:
\[ 4.463 \times 10^{11} \text{ years} = 446,300,000,000 \text{ years} \]
Thus, the half-life of uranium-238 is:
\[ 446,300,000,000 \text{ years} = 4.463 \times 10^{11} \text{ years} \]
In decimal form, it is:
\[ 446,300,000,000.0 \text{ years} \]
So, the answer for the half-life of uranium-238 in decimal form is:
446,300,000,000.0 years