SOLUTION: Ryan took 15 minutes to walk to school at an average speed of 70 m/min. His brother took 20 minutes to walk the same distance. Determine his brother’s average speed.
Question 1102271: Ryan took 15 minutes to walk to school at an average speed of 70 m/min. His brother took 20 minutes to walk the same distance. Determine his brother’s average speed. Found 3 solutions by ikleyn, josgarithmetic, greenestamps:Answer by ikleyn(52781) (Show Source): You can put this solution on YOUR website! .
1. The distance is 15 min * 70 m/min, calculated using Ryan's data.
2. The brother' speed is = 52.5 m/min.
This is a good example of inverse variation: the faster you move, the less time it takes; the slower you move, the more time it takes.
Ryan took 15 minutes to walk to school; his brother took 20 minutes. The ratio of the times is 3:4.
Since the distance is the same for both of them, the ratio of the speeds is 4:3.