Mr and Mrs Wallace hire a van for moving house. They see this advert in the local paper and decide to use this company. When they hand the van back, their bill comes to £59. How many hours did they ...

Computer scientists have devised an innovative and elegantly concise algorithm that can efficiently solve systems of linear equations that are critical to such important computer applications as image ...

She’s right—using simultaneous equations does get really complicated, and if you’d like to send me your work for the solution, I’d love to see it. But the system is also kind of a trick. Like a sudoku ...