Answer:
£12
Explanation:
Let the David's money be x
If David gets = x
Dan will get = 3x
Colin gets = 3x x 2
= 6x
So, the total money can be write as

So, now let's find the amount of money which David have

So, David will get £2
And now let's find the amount of money which Colin will get

He will get £12
Hope this helps you.
Let me know if you have any other questions :-):-)