To determine the system of equations that represents the situation with the machines A, B, and C, let's summarize the information provided:
- When all three machines A, B, and C are working, they produce 287 bolts per hour.
- When only machines A and C are working, they produce 197 bolts per hour.
- When only machines A and B are working, they produce 202 bolts per hour.
We can define the terms as follows:
- Let \( A \) be the production rate of machine A.
- Let \( B \) be the production rate of machine B.
- Let \( C \) be the production rate of machine C.
From the information provided, we can write the following equations:
- \( A + B + C = 287 \) (when all three machines are working)
- \( A + C = 197 \) (when only machines A and C are working)
- \( A + B = 202 \) (when only machines A and B are working)
Now, let's match this with the provided options:
- The correct system of equations is:
\[
A + B + C = 287
\]
\[ A + C = 197 \]
\[ A + B = 202 \]
Thus, the correct option is: A + B + C = 287, A + C = 197, A + B = 202.