Liam has some postage stamps with a total value of £2.80.
He has only 10p stamps and 20p stamps.
The ratio
number of 10p stamps : number of 20p stamps=4:5 \text{number of 10p stamps : number of 20p stamps} = 4 : 5 number of 10p stamps : number of 20p stamps=4:5Work out how many 20p stamps Liam has.
