Question 19
How many numbers between 2024 and 20240 which contain exactly two consecutive 9’s are there?
For example: 2099 and 9929 are included, but not 9295 or 1999.
For example: 2099 and 9929 are included, but not 9295 or 1999.
IMSO Science · IMSO 2024 Mathematics — International Short Answer