Multiple choice

A box contains $32$ coloured marbles. $8$ of them are red marbles and the rest are either blue or green marbles. A marble is drawn at random. Calculate the probability of drawing a marble which is not red in colour.

  1. $\dfrac {2}{3}$
  2. $\dfrac {5}{8}$
  3. $\dfrac {3}{4}$
  4. $\dfrac {7}{16}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Total marbles = 32. Red = 8. Not red = 32 - 8 = 24. Probability = 24/32 = 3/4.

AI explanation

The total number of marbles is 32, and the number of red marbles is 8. The number of non-red marbles is 32 minus 8, which is 24. Using the classical probability formula, the probability of drawing a non-red marble is 24 divided by 32. The result is 3/4.

Keep practicing — related questions