NumberCrunch Volume 1: Train your brain with 150 addictive sums by The Sun
From the pages of the nation's most popular daily paper comes a brand new puzzle that's sure to keep you and your family entertained for hours. "NumberCrunch, Volume 1" lets you take on the new craze that's as fun and simple as sudoku and see just how quick your wits are. There's no better way to train your brain and the more you do them the easier they get! See if you can complete each puzzle in under 30 seconds - or compete with others to see who's the sharpest. Just remember...No calculators!