Final answer:
To determine the number of times the Langs family stopped to refill their gas tank, calculate the total distance they traveled and divide it by their average mileage on one gallon of gas. Follow the step-by-step explanation for a clear understanding.
Step-by-step explanation:
To find out how many times the Langs family stopped to refill the gas tank, we need to calculate the total distance they traveled and then determine how many times they would need to fill up the tank based on their average fuel economy.
They drove 225 miles in total, with the last 45 miles at a speed of 65 miles per hour. So the remaining 180 miles were driven at a speed that we don't know.
Next, we need to find out how many miles they traveled on one gallon of gas. The problem states that on average, they travel 20 miles on one gallon of gas. We also know that their gas tank holds 15 gallons of gas. So if we divide the total distance traveled by the mileage on one gallon, we can determine how many times they would need to refill the tank.
Let's calculate:
- First, calculate the mileage for the last 45 miles using the formula: mileage = speed x time. The time for the last 45 miles is: 45 miles / 65 miles per hour = 0.69 hours. Therefore, the mileage for the last 45 miles is: 65 miles per hour x 0.69 hours = 44.85 miles.
- Next, calculate the mileage for the remaining 180 miles: total distance - mileage for the last 45 miles = 180 miles.
- Calculate the total mileage: mileage for the last 45 miles + mileage for the remaining 180 miles.
- Calculate the number of times they would need to refill the tank: total mileage / mileage on one gallon.
By following these steps, you should be able to determine the number of times the Langs family stopped to refill their gas tank.