To make Daniel have double the marbles compared to Ernesto, Ernesto needs to give Daniel 3 marbles.
To have Daniel end up with twice the number of marbles as Ernesto, Ernesto needs to give Daniel the difference in their current marble counts, which is 3 marbles (12 - 9 = 3).
After giving 3 marbles to Daniel, Ernesto will have 9 marbles left (12 - 3 = 9) and Daniel will have 12 marbles (9 + 3 = 12), making Daniel have twice as many marbles as Ernesto.
This scenario satisfies the condition where Daniel ends up with double the number of marbles as Ernesto.
https://brainly.com/question/296021