Adding and subtracting fractions. HASSAN:I bet this was a temple. OLIVIA:And this was a massive pillar. HASSAN:Does this go together with this? OLIVIA:Hmm, not sure. HYPATIA:Sorry it's a bit of a ...

It's easy to add and subtract fractions when the numbers on the bottom are the same. These are called the denominators. You can use equivalent fractions to make them the same. A common multiple of ...