Activity: Ask all the students in your class to write a 3-digit number. Choose any student from the room at random. What is the probability that the number written by her/him is divisible by 3? Remember that a number is divisible by 3, if the sum of its digits is divisible by 3.

Question

Philoid · Accepted Answer

Total Three Digits Number = 999 - 99 = 900

Number of 3 digits number divisible by 3 = $\frac{999}{3}-\frac{99}{3} = \frac{900}{3} = 300$

Thus, the probability that the number was written by her/him is divisible by 3 is given as:

$\frac{300}{900}=\frac{1}{3}= 0.33$