Answer:
served a greater variety of ages and then range
hope it helped!
Step-by-step explanation:
First you want to find out how many marbles you start with so it'd be 8+7=15. You start with 15 marbles. If you randomly drew a blue marble, it'd be 8:15 and if you drew a yellow marble without replacing the blue one, it'd be 7:14 or 50-50 chance.