Hi, puzzled01!
Together they can write a particular type of computer program in 16 hours. Mary can write the program by herself in 34.63 hours. How long will it take Tyrone to write the program alone?
Since they make 1 computer program in 16 hours, we know mary's time for 1 computer program and we want to find tyrone's time for 1 comp. prog... you can make this equation:\(\displaystyle \L \;\frac{1}{m}\,+\,\frac{1}{t}\,=\,\frac{1}{16}\)
...\(\displaystyle t\,=\,tyrone's\;time\,,\,m = mary's\;time\)
Since Mary can do it in 34.63 hours, we can fill that in for \(\displaystyle m\):\(\displaystyle \L \;\frac{1}{34.65}\,+\,\frac{1}{t}\,=\,\frac{1}{16}\)
Now we solve for \(\displaystyle t\). This is an ugly answer.
Subtract \(\displaystyle \frac{1}{34.65}\) from both sides:\(\displaystyle \L \;\frac{1}{t}\,=\,\frac{0.0336233035}{1}\;\Rightarrow\;t\,=\,\frac{1}{0.0336233035}\)