Answer:
£8
Step-by-step explanation:
If the ratio of money in Obi's wallet to Rudy's wallet one day was 5:2, then Obi had 5x and Rudy has 2x in their wallets.
Obi spent £20 and 5x-20 left. Obi now had £8 less than Rudy, thus,
[tex]2x-(5x-20)=8,\\ \\2x-5x+20=8,\\ \\-3x=8-20,\\ \\-3x=-12,\\ \\x=4.[/tex]
This means that initially Obi had £20 and Rudy had £8.
