Mastery: Reasoning and Problem-Solving
- True or false?
Adding three 2-digit numbers always produces a number over 50.
Adding three 2-digit numbers cannot produce 299.
There are three identical numbers which add to 252.
- Choose three consecutive numbers, e.g. 39, 40 and 41.
Repeat twice with different sets of consecutive numbers.
Can you see any relationship between the total in each case and the numbers added?
Simplify the numbers if it’s hard to spot a pattern.
Use a calculator to play with the numbers if necessary.
Does this work with all sets of three consecutive numbers, regardless of their size?
Can you explain why?
In-depth investigation: Dicey Operations
Adapt Game 1 to add three or four 2-digit numbers, aiming for a target total as close as possible to 200. Dicey Operations from nrich.maths.org.