Percentages Using Ratio Grids

If you are not already confident using RATIO GRIDS then watch this video first!

What is 35% of £14?

What is 15% of £85?

My savings target is £5500. I have saved £2640. What percentage have I saved?

Jo scored 65% in a test. She scored 26 marks. What was the test marked out of?

A tree was 15m tall in January. Now it is 18m tall. What is the percentage increase in height?

Another tree has grown 15% since January. It is now 46m high. What was its height in January?

Currency Conversion using Ratio Grids

Check out the Introduction to Ratio Grids if you are not already an expert!

When you are asked to do a currency conversion, you will usually be given an exchange rate first, as in this question:

“George changes some pounds into Euros. The exchange rate is £1=€1.18. If he changes £350 into Euros, how many Euros will he receive?”

Draw a simple Ratio Grid and give headings of £ and €. Put the numbers 1 and 1.18 in the correct columns. Then, the final number from the question, £350, goes in the £ column under the 1. Putting the numbers into their correct places is easy if you have headings! Put a ring around the empty space – that is where your answer will go.

In this grid, the 2 multiplying numbers are the “1.18” and the “350”, and you will divide by 1. So the sum will be 1.18×350÷1.

The answer is 413, and it is clearly in the Euros column, so give your answer as €413.

It’s easy if you get the headings right!

If you want lots of practice, Mr Corbett has a great set of currency conversion questions.

For lots of simple questions click here and the answers are here

Exam-style questions are here** and the answers are here. (Mr Corbett doesn’t use Ratio Grids so his methods won’t look the same, but the answers are all the same, obviously!)

** Some of these questions are really challening – they may require 2 ratio grids, so think carefully! If an exchange rate changes, you will need a new grid for the new rate.

Solving Ratio Problems

If you don’t yet know how to work out the 4th number in a ratio grid, watch this video first!

The videos on this page use the worksheet “Ratio Problems” which you can download:

Simplify a Ratio using a calculator
Split Money using a ratio
Wordy Ratio problem about socks
Wordy ratio problem given one of the values and not the total
Ratio problem sharing sweets