AlgebraMediumMeeting time of two trains approaching each other
Algebra practice question
Two trains are 300 kilometres apart on the same line and travel toward each other, one at 80 kilometres per hour and the other at 70 kilometres per hour. After how many hours do they meet?
Answer: 2
Together they close the gap at 80 + 70 = 150 km/h: 300 ÷ 150 = 2 hours.
Common wrong answers
- If you answered 1
- 1 halves the correct time.
- If you answered 30
- 30 comes from 300 ÷ (80 − 70), subtracting the speeds as if the trains moved the same way.
- If you answered 3.75
- 3.75 comes from 300 ÷ 80, using one train's speed.
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