Suppose you flip two coins. What is the probability of getting at most one heads? Give your answer as a reduced fraction.

To solve this problem, we first need to understand all the possible outcomes when flipping two coins. They are:

1. Heads, Heads (HH)
2. Heads, Tails (HT)
3. Tails, Heads (TH)
4. Tails, Tails (TT)

So, there are 4 possible outcomes.

Next, we need to identify which of these outcomes satisfy the condition of "at most one heads". These are:

1. Heads, Tails (HT)
2. Tails, Heads (TH)
3. Tails, Tails (TT)

So, there are 3 outcomes that satisfy the condition.

The probability of an event is calculated as the number of favorable outcomes divided by the total number of outcomes.

So, the probability of getting at most one heads when flipping two coins is 3 (favorable outcomes) divided by 4 (total outcomes), which simplifies to 3/4.