Unit 12

UNIT 12 MATH arithmetic n. Arithmetic is the part of math that deals with numbers. My teacher is good at teaching arithmetic. billion n. One billion is a very large number made up of a thousand million. The population of the world passed 7.5 billion in 2019. calculate v. To calculate is to work out the amount or number of something using math. Emma is trying to calculate how much money she has. compass n. A compass is a tool used in math which allows you to draw a perfect circle. The student drew a circle with her compass. divide v. To divide a number or thing means to split it into several smaller parts. Sue will divide the pie into eight pieces. division n. Division is the act of dividing numbers. The math teacher is trying to explain how division works. dozen n. A dozen is another way of saying twelve. The carton has a dozen eggs in it. equation n. An equation is a statement that the value of two mathematical expressions are equal. The man is trying to solve a difficult equation. even adj. An even number is one that can be divided into perfectly equal parts. Two, four, six, eight, and ten are all even numbers. formula n. A formula is a mathematical relationship or rule expressed in symbols. William wrote the formula on the blackboard.

fraction n. A fraction is a part of a whole number or thing. One half is an example of a fraction. graph n. A graph is a picture that shows us numbers or quantities. These graphs tell us everything about the company's sales. less adv. If there is less of something, it is smaller in size or value than another. She has less water than he does. minus prep. Minus is the part of a sum that tells us to take something away. Seven minus one equals six. multiply v. To multiply is to increase a number by adding that number to itself a certain number of times. If you multiply two by two, you get four. ordinal n. An ordinal is a type of number which tells you where something comes in a list. First, second, third are all ordinal numbers. percent adv. Percent is a number or value compared to a total value of 100. Nuclear power provides 14 percent of the world's energy. plus prep. Plus is the part of a sum which says a number will be added. One plus one equals two. quarter n. A quarter is one of four equal parts of a whole number or thing. Somebody ate one quarter of the burger. subtract v. To subtract is to take one number away from another. If you subtract three from seven, you have four.

The Math Test I'm so worried about the big math test this afternoon. I'm struggling even to remember what a fraction is! A fraction is part of a whole number, like a quarter or a half. Just think of it like this: if you divide an apple pie into four equal pieces, then you have four quarters! Actually, I'm OK with graphs. It's everything else that I'm worried about. I mean equations, formulas--they seem so complicated. I'm much less confident about them. Those are both just types of sums which are used to prove if an idea is right. Anyway, I think this test will be focused on basic arithmetic, and I'm sure you know how to add, subtract, and multiply, right? Yeah, I'm pretty confident with all of those-and with division: that's just chopping stuff up into pieces! Anyway, I know you'll do great. You're in the top two percent of students. Well, no. Last time, I was tenth in the class. You know what "tenth" is, don't you, Max? Sure, it's an ordinal number. Right. Do you have all the equipment you need? I think so. I've got a compass in case we need to draw circles, but actually, I don't have a pencil! You're terrible, Max. Here I have several spares-you can borrow one of mine. Thanks, Jen. You're one in a billion! Hey, that's a fraction, right? Haha, there's hope for you yet!