3 hours and 30 minutes
1) Let's assume that the speed that Bruce reads is constant. So we can write the following proportion:
[tex]\begin{gathered} 1h----40 \\ x----140 \end{gathered}[/tex]2) From that we can write out the following ratios and then cross multiply them:
[tex]\begin{gathered} \frac{1}{x}=\frac{40}{140} \\ 40x=140 \\ \frac{40x}{40}=\frac{140}{40} \\ x=\frac{7}{2}=3.5 \end{gathered}[/tex]Hence, it will take him 3 hours and 30 minutes
