Question

An astronaut has to watch two videos before the next mission. Video C is 420-minutes long, out of which the astronaut has finished watching $270$ minutes of it. The duration of video $D$ is half the duration of the part of video $C$ that has not been watched yet. Calculate the duration of video $D$.

• A. 75 minutes
• B. 150 minutes
• C. 300 minutes
• D. 210 minutes

Answer 1

The correct option is A 75 minutes

Total duration of video $C=420$ minutes
Duration of video C watched by the astronaut $=270$ minutes
To determine the duration of video $D$, we need to subtract $270$ from $420$, and then divide the result by $2$.
Duration of video $D=(420-270)÷\frac{1}{2}$


Hence, the duration of video B is $75$ minutes.