Final answer:
Amir and Rosie's marble-sharing ratio translates to 10 marbles for Amir and 35 for Rosie, with Rosie having 25 more marbles than Amir.
Step-by-step explanation:
Amir and Rosie share marbles in the ratio of 2:7. If Rosie receives 35 marbles, to draw a bar model, make a bar that is 7 units long to represent Rosie's marbles and one that is 2 units long to represent Amir's marbles. Each unit represents the same number of marbles. Since Rosie received 35 marbles and has 7 units, each unit is 35 divided by 7, which is 5 marbles per unit.
Now to find out how many marbles Amir received: Because the ratio is 2:7, and each unit is worth 5 marbles, Amir receives 2 units times 5 marbles per unit, which equals 10 marbles. For part C, to find out how many more marbles Rosie got than Amir: Rosie received 35 marbles and Amir received 10 marbles, so Rosie received 35 - 10 = 25 more marbles than Amir.