Which comes first? (BIDMAS)

Hello, and welcome to Myriora Maths! What is two plus three times four? Some people say twenty. Some people say fourteen. They can't both be right! Maths has a rule for which part comes first.

The rule is: multiply before you add. So do three times four first: that's twelve. Then add the two: fourteen.

Why that rule? Think of buying apples. You get two loose apples, and three bags of four apples. Three bags of four is twelve apples, plus the two loose ones: fourteen. The times part belongs together, like a bag!

Here's the full order, called bid mass. B is for brackets: they always go first. I is for indices, which means powers, like squared. Then D and M: divide and multiply. Then A and S: add and subtract.

Here's a secret. Divide and multiply are a team, and they're equally important. Add and subtract are a team too. When team partners are together, just work from left to right. Twelve divided by three, times two. Twelve divided by three is four, and four times two is eight.

Brackets jump the queue. Two plus three, in brackets, times four. Do the brackets first: five. Then times four: twenty! So brackets can change the answer.

Let's try one together. What is ten take away two times three? Remember: times first! Say it out loud!

Two times three is six. Then ten take away six is four!

Here's a question that catches lots of people. What is two plus three times four? Some people go from left to right: two plus three is five, times four is twenty. But multiply comes before add! Three times four is twelve, plus two is fourteen.

Your turn! What is five plus six divided by two? Pick the right card. You've got fifteen seconds, or pause the video. Go!

Time's up! Divide before you add. Six divided by two is three. Five plus three is eight!

Quick review. Multiply and divide before you add and subtract. The full order is bid mass: brackets, indices, divide and multiply, add and subtract. Team partners go from left to right. And brackets always go first. See you next time!