It's been a very long time since I challenged readers with a sum from the NumberWizFP game, the game that treats hexadecimal and octal numbers with the respect they deserve.
Here's a sum:
Using addition, subtraction, multiplication and division, how do you make D90H out of these six numbers 2, 3, 4, 9, 40H, 80H ?
You're welcome to mail your solution to admin at proctele.se, or in the comments below.
Remember: You can buy NumberWizFP in the App Store and generate as many sums as you like. For this app you'll have to fork out the equivalent of a full cup of coffee ;-)