If you roll a fair six-sided die and a fair four-sided die, what is the probability that neither die shows a 1?

Answer in fraction form: 5/8
Answer in decimal form: 0.625



Explanation:

There are 5 sides that aren't labeled "1" out of 6 total. So the probability of not rolling a "1" on the six-sided die is 5/6

Similarly, there are 3 sides that aren't labeled "1" out of 4 sides on the four-sided die. The probability of not rolling a "1" for this die is 3/4

Multiply the fractions
(5/6)*(3/4) = (5*3)/(6*4) = 15/24 = 5/8

The answer in fraction form is 5/8 which converts to 0.625 (use long division or a calculator)

Note: the multiplication of probabilities works because the two events (of rolling each die) are independent