The 4 digits of 2022 can be used to make numbers. You decide what to allow. Here we allow the four standard binary operations of +, -, x and ÷, with brackets for clarity. Then we introduce Concatenation, so 20 can be used; after that come powers and factorials. We’ve made 72% of numbers 1 to 50 keeping the digits in the order 2022. Another 6 (12%) could be found using the digits in some other order. Eight have not been found.

UPDATE – solutions for 13 (not in order), 36 in order and 40 (in order but uses square root) now found by R Backé, Sargent Park School, Winninpeg, Canada (and given only in the Excel file).

The following files are available

- Teacher notes in pdf form (contain answers and data collection sheets)
- Excel file with answers
- ActivInspire Flipchart of classroom slides
- PowerPoint containing classroom slides