We should put the names aside to begin with and just look at the ratio and the price. In order to find out how much the ratio 3, the ratio 4 and the ratio 8 are worth, we need to find out how much the ratio 1 is worth. We do this by adding all the numbers in the ratio together, then dividing the money with this number.
So in this example, 3 + 4 + 8 = 15.
Then 240 / 15 = 16
This means that the ratio 1 is 16.
Now we should go back and look at the names in the question again. It asks us how much more money than Lisa (ratio 3) does Punita (ratio 8) get.
Ratio 3 means that it is 3 times larger than ratio 1. So we have the sum 16 x 3 = 48. This is how much Lisa gets.
We do the same thing for Punita now, but as it is 8 times larger, the sum is 16 x 8 = 128.
The penultimate step now requires you to subtract the difference between Lisa and Punita's money. So 128 - 48 = 80.
In your final step where you write down your answer, don't forget to write down the units, in this case pounds. So the answer is £80.