Answer:
12.5%
Explanation:
Step 1:
We need to find out the percentage of picking a marble that is red. In total, there are 10 marbles, and there are 5 red. To find the probability of picking a red marble, you need to do:
# of red / total marbles.
There are 5 red marbles and 10 total marbles, so the probability of getting a red marble is 5/10, and you can simplify it to 1/2 (5/10 * 5/5).
Step 2:
Now we can start finding the probability of finding the probability of choosing three red marbles in a row. Since we need to find the probability of choosing red marbles three times, you can multiply 1/2 by itself 3 times (1/2 * 1/2 * 1/2).
1/2 * 1/2 * 1/2 = 1/8
Step 3:
Now we need to convert the fraction into a percentage. You can find the percentage by dividing 1 by 8. You should get 0.125, and you can multiply 0.125 by 100, and your final answer should be 12.5%.