Question

There are 5 red marbles, 8 blue marbles, and 12 green marbles in a bag.

What is the theoretical probability of randomly drawing a red marble?



25%

20%

62.5%

41.7%

Answer 1

Total number of marbles:
5+8+12 = 25

Probability of drawing red marble = red/total
= 5/25 =1/5

Percentage of drawing red marble: 1/5 x 100 = 20%

Ans: 20%

Answer 2

To find the percentage always multiply whatever decimal number you have by 100%
1) 5 + 8 + 12 = 25 (total number in bag)
5/25 x 100% (because you're trying to find probability of red)
= 20%

2) 5 + 8 = 13 (# of red AND blue)
13/25 x 100% (divide out of the total)
=52%

3) 5/25 = 0.2 x 12/25 = 0.48 (find probability of drawing red and green)
0.2 x 0.48 x 100%
= 9.6%

4) 10 + 12 + 28 = 50 (to find total number of trials)
28/50 x 100%
= 56%

5) 5 x 7 (number of sections on first spinner multiply by # of sections on second spinner)
= 35Its B 20%