Question

In a throw of a pair of dice, find the probability of getting a sum less than 6.

Answer 1

Given: A single throw of two fair six-sided dice. Total possible equally likely outcomes = 6 × 6 = 36.

Step-wise calculation:

1. Sums less than 6 are 2, 3, 4, 5.

2. Count favourable outcomes:

Sum 2: (1, 1) → 1 outcome

Sum 3: (1, 2), (2, 1) → 2 outcomes

Sum 4: (1, 3), (2, 2), (3, 1) → 3 outcomes

Sum 5: (1, 4), (2, 3), (3, 2), (4, 1) → 4 outcomes

4. Total favourable

= 1 + 2 + 3 + 4

= 10

5. Probability = `"Favourable"/"Total"`

= `10/36`

= `5/18`

= 0.2778

Required probability = `5/18`.