A box contains 12 identical balls of which 5 are red, 4 blue, and the rest are green. If a ball is selected at…

Analyze the question: We have 12 balls in total. We know the number of red and blue balls, and the "rest" are green. We need P(green).

Concept: Probability = (number of favourable outcomes) ÷ (total number of outcomes)

Solution:

1. Number of green balls = Total − (Red + Blue) = 12 − (5 + 4) = 12 − 9 = 3

2. P(green) = Number of green balls ÷ Total number of balls = 3/12 = 1/4

Answer: The correct option is **D.

Tip: When a question says "the rest," subtract the known quantities from the total first. Always simplify your fraction at the end (3/12 → 1/4), because the options are usually given in simplest form. A quick check: the probabilities of all colours must add up to 1: 5/12 + 4/12 + 3/12 = 12/12 = 1 ✓.