Math

Posted by MichikoNakamura Sat, 24 Nov 2007 17:00:54 GMT

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Let's begin by reading this conversation:

Michiko: Michael, could you give me the receipts from today's shopping. I'm going to record it in my checkbook.
Michael: OK, here you are. You spent 52 dollars and 12 cents at Liberty House and 89 dollars and 35 cents at Foodland.
Michiko: So what does that add up to?
Michael: Well, let's see. That adds up to one hundred forty one dollars and forty seven cents.
Michiko: I had 750 dollars in my checking account before. If I subtract one hundred forty one, forty seven that comes out to six hundred eight dollars and fifty three cents.

Is this conversation familiar to you? The checkbook is only one example of how useful math is in everyday life. In the conversation above, Michiko said:

"I'm going to record it in my checkbook."

That means she is going to write down how much money she spent. Finally, Michiko asked:

"What does that add up to?"

"Add up" means addition. That's "Tashizan" in Japanese. Addition is adding numbers together to find the total. Like "1 plus 1 equals 2" and so on. You can add small numbers or big numbers.

Read these example sentences:

"Two plus three equals five"

"Two and three add up to five"

How much money did she spend today? 141 dollars and 47 cents. Michiko had to subtract that number from 750. She said:

"If I subtract one hundred forty one, forty seven that comes out to six hundred and eight dollars."

Here's a simpler example:

"If I subtract 35 that comes out to 5"

Subtraction is the opposite of addition. It means to take away from. In English, we say "minus".   For example:

"What does seven minus three equal?"

Another way to say the same thing is:

"What is seven take away three?"

So how do you answer those questions we gave above. Read these
example sentences:

"Seven minus three equals four"

"Seven take away three is four"

Read this next conversation:

Michiko: That was a good dinner, wasn't it?
Michael: It sure was.
Michiko: Where's the bill?
Michael: Oh, it's right here.
Michiko:   Did you check it to make sure it's correct?
Michael: Let me see. That's 1combination plate at $8.50. I had the same thing so that's $8.50 times 2 equals $17 plus tax.

Did you hear the multiplication in this conversation? You might need to use multiplication any time or anywhere. Even in a restaurant.
For example:

"$8.50 times 2 equals $17"

"8.50 multiplied by 2 is 17"

Multiplication is very useful, especially when you go shopping or when you are at a restaurant.

Read this next conversation:

Michael: If you buy 12 loaves of bread at 2 dollars each, how much is that?
Michiko: Let's see. 12 times 2. Where's my calculator?

Read these example conversations:

Michiko: How much is 12 loaves of bread at 2 dollars each?
Michael: 12 times 2 equals 24.
Michael: 12 multiplied by 2 is 24.

Michiko: How much is 7 cans of coke at 60 cents each?
Michael: 7 times 60 equals 420.
Michael: 7 multiplied by 60 equals 420.

Another important calculation is division or "divided by".   Read this next conversation:

Michael: Michiko, I bought the tickets for the basketball game next week.
Michiko: How much were they?
Michael: Well, I bought two tickets for 45 dollars.   So 45 divided by 2 equals 22.50.   The tickets were 22 dollars and 50 cents each.
Michiko: OK. Here's your money.
Michael: Thank you.

In this conversation, Michael bought two tickets for 45 dollars. If you want to divide this number by the number of tickets, you can say:

"45 divided by 2 equals 22.50"

Now, read this short conversation:

Michael: I bought 4 apples for 2 dollars. How much is one apple?
Michiko: What's 2 dollars divided by 4?
Michael: It's 50 cents.

When you use division you can say:

"divided by"

or

"divided into"

For example:

"35 divided by 7 equals 5"

"35 divided into 7 equals 5"

Now read this short conversation:

Michiko: Would you like a piece of pizza?
Michael: Sure, in fact I'll take two pieces if you have enough.
Michiko:   Yes. We have plenty. Please eat as much as you want.

There was plenty of pizza so Michiko said:

"Please eat as much as you want."

Another way to say the same thing is:

"Please eat as much as you can"

or

"Please eat as much as you like"

The form of both of these sentences is "as much as". Read this example sentence:

"As much as possible, I want to be a good student"

Now let's read this next conversation:

Mom: Son, would you like another helping?
Boy: Yes, I would. This is my third helping.
Rona: Mom, I've only eaten 1helping. How come he gets to eat three times as much as me but he's only half my size?

Did you understand that? Her brother is only half her size. Thatmeans she is two times bigger than him.   That's what 3 times as much means. Read this example sentence:

"My brother eats three times as much as me"

You can also say:

"twice as much as"

or

"three times as much as"

For example:

"My weight is twice as much as my daughter's."

Another sentence you could use is:

"My father is two times heavier than I am."

Most of you probably learned it when you were in elementary school. It's called "Fractions".   Fractions are when you take only part of a whole number.    Fractions are very useful in certain situations. Read this example conversation:

Michael: Would you like to split this chocolate pie?
Michiko: No, that's too much. Just give me one fourth. You can eat the other three fourths.
Michael: I can't eat that much. I'll just eat one fourth and take the rest home.

In fractions, there are two numbers. The bottom number is the total number. Like in the example of the pie, there are 4 pieces. The top number is how many pieces you want.

Read this short conversation:

Michiko: I baked a pound cake. Would you like some?
Michael:   I'll take 1/5 please.

Michiko: Would you like to eat an apple?
Michael: OK, can I have 2/3 please.

Michiko: Did you eat some of the casserole?
Michael: Yes, I ate about a quarter of it.