Primary 4 tackle the Deputy First Minister’s Maths Challenge
Primary 4 decided to take a practical approach to this problem and took the problem outdoors with a chart and some chalk. We split into teams of 3 (one team had Teddy to help as they only had 2 people in it). We recreated the stairs and solved the problem, including that Ross’s left foot only ever landed on an odd number, whilst Elena’s left foot never landed on an odd number, so the answer to c) was that it was impossible.
The Problem - Stepping Up Three friends visit a museum and walk up a flight of stairs. Ross goes up one step at a time starting with his left foot on the first step. Elena goes up two steps at a time starting with her left foot on the second step and Tom starts with his left foot on the third step and goes up three steps at a time. Investigate these questions and explain your answers: (a) Which is the first step that all three will tread on? (b) Which is the first step that all three will tread on with their right foot? (c) Which is the first step that all three will tread on with their left foot?
The worked together to create a table to prove the answers:
|
Step
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
| 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | |
|
Ross
|
L | R | L | R | L | R | L | R | L | R | L | R |
| L | R | L | R | L | R | L | R | L | R | L | R | |
|
Elena
|
L | R | L | R | L | R | ||||||
| L | R | L | R | L | R | |||||||
|
Tom
|
L | R | L | R | ||||||||
| L | R | L | R |
