Answer:
10 sweets.
Explanation:
So all of them share the sweets in a ratio of 4:2:3. Since Gavyn gets 10 more sweets than Stephen, and the ratio of Gavyn's sweets to Stephens sweets is 4:3, which means that x=10. To clarify, a ratio can be written as 4x:3x, so x=10. So now you do Richards ratio (2x) and you just plug in x and you get 20. So Richard gets 20 sweets.