Question: 1) An aircraft carrier made a trip to St. Vincent and back. The trip there took ten hours and the trip back took six hours. It averaged 25 mph on the return trip. Find the average speed of the trip there.
A) 15 mph B) 20 mph
C) 14 mph D) 10 mph
1. **State the problem:**
We need to find the average speed of the trip there, given the return trip speed and times for both trips.
2. **Given data:**
- Time going there: $t_1 = 10$ hours
- Time returning: $t_2 = 6$ hours
- Speed returning: $v_2 = 25$ mph
- Speed going there: $v_1 = ?$
3. **Key formula:**
Speed = Distance / Time
4. **Important rule:**
The distance going there and back is the same, so:
$$d = v_1 \times t_1 = v_2 \times t_2$$
5. **Set up the equation:**
$$v_1 \times 10 = 25 \times 6$$
6. **Calculate the right side:**
$$v_1 \times 10 = 150$$
7. **Solve for $v_1$:**
$$v_1 = \frac{150}{10}$$
8. **Simplify the fraction:**
$$v_1 = \cancel{\frac{150}{10}} \Rightarrow v_1 = 15$$
9. **Answer:**
The average speed of the trip there is $15$ mph.
**Final answer: A) 15 mph**