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© David Lawrence 2000

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Learn the basics of Algebra in 3 minutes
See if you can folow the question below and how we deal with it.


We are going to go back and look at Question 1 and go through it more slowly and in greater detail.

First, read the question.

Question 1:

June has 2 more cookies than Robert. June and Robert combined have 8 cookies. How many cookies do they each have?

Then read it again.

June has 2 more cookies than Robert. June and Robert combined have 8 cookies. How many cookies do they each have?

There are two people mentioned in the question, June and Robert.

They both have some cookies, but the question doesn't tell us us how many.

But the question does tell us two things.

1. - That June has 2 more cookies than Robert

2. - That if they both put their cookies together in one pile there will be 8 cookies

The question wants us to determine how many cookies each of them has.

The first thing we do is identify the person we don't know anything about.

That's Robert isn't it? Because we know something about June - she has 2 more cookies than Robert.

After the question we then write this line:

Let 'x' equal the number of cookies Robert has.

The 'x' represents a number but at this stage we don't know what the number is.

Algebra is a way to find out that number from the other data we are told.

In the question we are told that June has 2 more cookies than Robert.

We've already decided that Robert has 'x' cookies, so June must have ('x' + 2) cookies. We put it inside brackets to show that it's one number represented by a number and a letter.

The combined pile of cookies will = The cookies Robert has + The cookies June has.

We can now write this in the form of an equation and then solve it:- (An equation means just two things that are equal)s

The equation is as follows:

The combined pile of cookies will = The cookies Robert has + The cookies June has

Written numerically this becomes:

- The Pile------ -Robert--------June
---- -- - -- ---\---- / /-- - - - - - /
----------------- 8 = x + (x + 2)

We can add the 'x's together so the equation becomes:------------

----------------- 8 = 2x + 2

-------------8 - 2 = 2x --------(Take 2 away from each side)

---------- -------6 = 2x----------(Bring to one number)

----- ----- 6 ÷ 2 = x--------(Divide by 2 to get a single 'x')

---------- -------3 = x------ (x = Robert)

Answer 1:

Click on the answer below you believe is the correct one.

Answer to question 1:

'A' - Robert has 3 cookies. June has 6 cookies

'B' - Robert has 2 cookies. June has 4 cookies

'C' - Robert has 3 cookies. June has 5 cookies

'D' - Robert has 5 cookies. June has 3 cookies