Sometimes it is useful to be able to divide different amounts into a given ratio.  You might be dividing money, lollies or other things among some friends who have helped you do something, but some friends may have helped more than others so you want to give them a bit more than the others.

Rather than guessing, you can use your trusted Kid's Rule to work out exactly how much each person should receive.

 Worked Example:

You and a friend have just finished mowing a large lawn.  Since you supplied the fuel, you both agree that the payment should be divided in the ratio 4:3 in your favor.  If the owner of the property pays $56, how much do each of you receive?

In this type of problem we are given the ratio, in this case 4:3.  This means that the amount, $56 must divided into 7 (4+3) equal parts.  Four of those equal parts are given to you and the remaining three are given to your friend.  So our first step is to set the slide to divide 56 by 7.

1. Line up C56 with D7.
   (This set up $56 divided by 7.)
2. Move the cursor to C4 and read D32.
   (This means that 4 parts of $56 is $32.)
3. Move the cursor to C3 and read D24.
   (This means that 3 parts of $56 is $24.)

 The answer to our problem is that you receive $32 and you friend receives $24.

Note that the two amounts must add up to the original amount before it was divided.  Indeed, $32+$24=$56.  You should also note that the ratio $32:$24 is the same as 4:3.  You can set your slide rule to check this ...

1. Line up C32 with D24.
2. Move the cursor to C4 and read the result D3.

Now let's try some practice questions, by clicking here!