Timing
Problem
Is it possible and if so what date did they meet?
These two problems were suggested by Lim Yi Jia from The Chinese High School, Singapore.
Getting Started
What could you jot down or draw to help you?
What will Tom's watch say when the time is 7.57?
What will John's watch say when the time is 7.57?
Student Solutions
- Office On Time - As Katherine from the International School, Brunei
says the answer depends on the bus driver's watch and whether the
bus is on time! Good solutions came from Katherine; from Ben, from
a large number of pupils at The Mount School, York; and from Barry,
Eaton School, Norwich; James, Hethersett High School, Norwich; Kang
Hong, Chinese High School, Singapore; and Steve, Bedlington High
School, Northumberland.
Only Tom will catch the bus to work. He will arrive at $7.42$ if he wants to get there $3$ minutes early. John will get there at $8.12$ if he wants to get there $3$ minutes early. This is because, say the exact time was $7.50$ by Tom's watch it would be $8.00$, but he thinks this is $5$ minutes slow, so he would believe the time was $8.05$. This gives him 15 minutes so if he wanted to arrive at the bus stop at $7.57$ by his watch, the actual time would be $7.57 - 15$ minutes $ = 7.42$. The same happens for John but in the opposite way therefore he arrives $15$ minutes later, at $8.12$. (Steve, Bedlington High School, Northumberland)
- Hawaii - Two days before the meeting he is 25
years old and next year he will be 28.
Image
Well done Suzanne, Helen, Charis, Lyndsay, Nisha and Christiane from The Mount School York, and others from The Mount School and especially Christiane who did the time line. Well done also to Kang Hong from The Chinese High School, Singapore, Laura, Ipswich High School; James, Hethersettt High School, Norwich; Alan, Bedlington High School, Northumberland.