There are 8 balls in an opaque box: 3 black and 5 white. Three balls are taken out at random.

There are 8 balls in an opaque box: 3 black and 5 white. Three balls are taken out at random. What is the probability that all the balls taken out are white?

The probability that the first marble is white is 5: 8 = 0.62.
The probability that the second is white is 5: 7 = 0.71.
The probability that the third is white: 5: 6 = 0.83.
Total, the probability that all 3 taken out balls are white: 0.62 * 0.71 * 0.83 = 0.36.
We translate into percentages 0.36 * 100 = 36%
Answer: Probability 36%