Answer:
Part A: The two buses leave the bus station at 7 : 15 am
Part B: The steamboat travels 25 miles per hour
Explanation:
* Lets explain how to solve the problem
Part A
- Buses begin their routes at 6 am at a bus station
- Bus A leaves every 75 minutes
- Bus B leaves every 15 minutes
- We want to know the next time Bus A and Bus B will leave the bus
station at the Same time
# Bus A
∵ Bus A leaves every 75 minutes
- Lets change 75 minutes to hours and minutes
∵ 1 hour = 60 minutes
∴ 75 minutes = 75/60 = 5/4
- Change 5/4 to mixed number
∵ 5/4 = 1 1/4
∴ 75 minutes = 1 1/4 hours
- Lets change 1/4 hour to minutes
∴ 1/4 × 60 = 15 minutes
∴ 75 minutes = 1 hour and 15 minutes
∵ Bus A leaves the station at 6 am
- Add 1 hour and 15 minutes to that time
∵ 6 + 1 : 15 = 7 : 15
∴ Bus A leaves the station nest time at 7 : 15 am
# Bus B
∵ Bus B leaves every 15 minutes
∵ Bus B leaves the station at 6 am
- Add 15 minutes to 6 am
∴ Bus B leaves the station next time at 6 : 15 am
- Add another 15 minutes for next time
∴ Bus B leaves the station next time at 6 : 30 am
- Add another 15 minutes for next time
∴ Bus B leaves the station next time at 6 : 45 am
- Add another 15 minutes for next time
∵ 15 + 45 = 60 ⇒ add 6 by 1 because 60 minutes = 1 hour
∴ Bus B leaves the station next time at 7 am
- Add another 15 minutes for next time
∴ Bus B leaves the station next time at 7 : 15 am
- The 2 buses leave the station at the same time again at 7:15 am
* The two buses leave the bus station at 7 : 15 am
Part B
- It takes a steamboat 12 hours to travel 300 miles
- We need to find how many miles it travels per hour
∵ The steamboat travels 300 miles in 12 hours
- Divide the distance by the time to find its rate
∵ 300 ÷ 12 = 25
- That means it travels 25 miles per hour
∴ The steamboat travels 25 miles per hour