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We answer your questions about… math!


We've been getting so many great questions through the Question Machine! Phew! You're really interested in a lot of things. We thought we'd group some of the questions together and answer them in a big bunch. So here are your questions about... math!

Question 1

Vina asks why numbers are called numbers - that's actually a complicated answer

What we think of as "numbers" are actually three different things: numbers, numerals and digits. So what's the difference between the three? A number is a count or measurement that you can picture in your head, a numeral is a symbol or the name you call that number and a digit is each symbol in that numeral. Let's work this out and make it clearer:

  1. Think of a number in your head. That number could be made up of oranges, slices of pizza or even puppies. That idea that you have in your head is called a number.
  2. Now write down what you were thinking. If you were thinking of eighteen items then write it down as "18." This is called a numeral. Numerals can be any length.
  3. Now look your numeral. In our numeral "18," the "1" and the "8" are each called a digit.

Don't worry if you mix up your numerals and numbers since most people use the word "number" for digits and numerals as well.  

Question 2

Jael asks is zero a number - it's both a number and a placeholder

So how can zero be two different things? Zero is a placeholder because it's used in numbers to show an absence of something: in the number 405, the number zero is used to show us that there are no tens in the number. You can tack on zeros to the end of a digit to show it getting bigger: 200 is bigger than 20 which is bigger than 2. But zero is also a number and you can add, subtract and multiply by it (just don't try to divide by it). Zero, the number, also sits comfortably between +1 and -1 on the numerical scale. 

Question 3

Anya asks what is zero divided by zero - you can't divided zero by zero since the answer is undefined

In math, division is about splitting something up into equal parts. For example, you have 12 pieces of chocolate and you want to split the chocolate up among you and two other friends — 12 pieces divided by 3 people equals 4 pieces for each person. But, the number zero means that you have none of something. So how do you split no chocolate with no friends?  

Question 4

Baha asks how long it will take to walk from Ohio to Montreal - Google Maps says it would take 216 hours

Of course, that would be 216 hours with perfect traffic, no stops for snacks or naps and using the route designated as optimal by Google Maps. Plus, you'd probably need some time at the border to explain to Canada Customs why you're walking such a long distance.

Want more answers? We've got 'em!


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