Question 700187
The ratio 2:5 means mark has 2 'parts' and john has 5 'parts'.
If john has 20 coins this means that 20 coins is 5 parts.
So we find that 1 part is 4 coins ({{{20/5}}}).
If 1 part is 4 coins, then 2 parts is 8 coins.
So mark has 8 coins.