If each frame of a motion picture film is 35 cm high, and 24 frames go by in a second, estimate how many frames are needed to show a two hour long movie.

Options

A. 1400
B. 25 000
C. 50 000
D. 170 000

Answer

To solve the problem of how many frames are needed to show a two-hour long movie, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the given information**:
- Each frame of the film is 35 cm high (this information is not necessary for the calculation).
- There are 24 frames shown per second.

2. **Convert the duration of the movie from hours to seconds**:
- We know that 1 hour = 60 minutes and 1 minute = 60 seconds.
- Therefore, 1 hour = 60 minutes × 60 seconds/minute = 3600 seconds.
- For 2 hours, we calculate:
\[ 2 \text{ hours} = 2 \times 3600 \text{ seconds} = 7200 \text{ seconds} \]

3. **Calculate the total number of frames for the entire duration**:
- Since there are 24 frames per second, we can find the total frames for 7200 seconds by multiplying:
\[ \text{Total frames} = 24 \text{ frames/second} \times 7200 \text{ seconds} \]
- Performing the multiplication:
\[ \text{Total frames} = 24 \times 7200 = 172800 \text{ frames} \]

4. **Conclusion**:
- Therefore, the total number of frames needed to show a two-hour long movie is **172800 frames**.