12 Easy Math Tricks You’ll Wish You’d Known This Whole Time
Did you enjoy your dining service? Leave your server a 20 percent tip with this easy math trick. According to Kate Snow, ...
BBC4 年
Four everyday Maths tips and tricks from celeb whizzes
Practise Rachel's method for finding percentages and you'll know if you've got a real bargain on your hands in no time. Check out another double-digit multiplication trick with Rachel's maths hack ...