A box contains 7 green, 4 red and 3 blue marbles. One marble is pulled from the box without looking, what is the probability of not getting a red marble?

Work:7+4+3=14
4/14=2/7
Or
7+3=10
4/10=2/5
Which one is correct.

1 answer

Neither:

7+4+3=14

7+3=10

10/14 (or 5/7) marbles are not red

so you have about a 71% chance of not getting a red marble