÷ 10, ÷ 100, ÷ 1000

Hello, and welcome to Myriora Maths! People say: to divide by ten, just take off a zero. That works for four hundred and sixty. But what about thirty-five divided by ten? There's no zero to take off! Let's see what really happens.

Here's a place value chart. Four thousand, five hundred: four thousands and five hundreds. Divide by ten, and every digit moves one place to the right. Four hundreds and five tens: four hundred and fifty.

Why to the right? Divide by ten, and every hundred becomes a ten. Every ten becomes a one. So each digit is worth ten times less: that's one place to the right.

Divide by a hundred, and the digits move two places. Four thousand five hundred divided by a hundred is forty-five. Divide by a thousand, and they move three places. Four point five!

Now, thirty-five divided by ten. The three moves into the ones. The five moves past the decimal point, into the tenths. Three point five! The digits moved. The decimal point stayed still.

Sometimes you need zeros to hold places. Seven divided by a hundred. The seven moves two places right, into the hundredths. Now the ones and the tenths are empty. Fill them with zeros: zero point zero seven.

This is really useful for measuring. There are a hundred centimetres in a metre. So two hundred and fifty centimetres, divided by a hundred, is two point five metres. There are a thousand grams in a kilogram. So three thousand four hundred grams is three point four kilograms. And three hundred and seventy-five pence, divided by a hundred, is three pounds seventy-five.

Let's try one together. What is six hundred and twenty divided by ten? How many places do the digits move? Say it out loud!

Divide by ten: one place to the right. Sixty-two! Well done if you said sixty-two!

Here's a question that catches lots of people. What is thirty-five divided by ten? Some people try to take off a zero. There isn't one, so they just cross off the five, and write three. But that loses the five! Move the digits instead: three point five.

Your turn! What is eighty-two divided by a hundred? Pick the right card. You've got fifteen seconds, or pause the video. Go!

Time's up! Divide by a hundred, and the digits move two places to the right. The eight moves into the tenths, and the two into the hundredths. It's zero point eight two!

Quick review. Divide by ten, a hundred, or a thousand, and the digits move one, two, or three places to the right. The decimal point stays still. Zeros fill the empty places. And that's how you change centimetres to metres, grams to kilograms, and pence to pounds. See you next time!