Direct proportion

Direct proportion problems

using the unitary method

DIRECT PROPORTION PROBLEMS

• Direct proportion means that as one thing goes up, the other things goes up at the same rate

• For example, if 2 bananas cost 26p, then 4 bananas will cost 52p (double the number of bananas is double the cost)

DIRECT PROPORTION

Money problem

DIRECT PROPORTION

Often there isn't an obvious scale factor to take you straight to the answer

DIRECT PROPORTION

Here we need to use the UNITARY method, which means finding how much for ONE item

DIRECT PROPORTION

Once you know how much is in ONE pot, you can use this to find out the answer

Fill in the Blank

If 15 bricks weigh 150kg.

What would 8 bricks weigh?

Fill in the Blank

Sam earns £21 for 3 hours work.

How much would he earn if he worked 5 hours?

Fill in the Blank

If 4 coaches can carry 168 passengers,

how many passengers can 3 coaches carry?

DIRECT PROPORTION

So, all you have to do is DIVIDE to find out how much for ONE item, and then MULTIPLY to find the answer you are looking for

DIRECT PROPORTION PROBLEMS

There are quiet a lot of applications for this unitary method:

>Recipe problems

>Value for money

>Currency exchange