Which of the following numbers is completely divisible by 3?

Here are the solutions to the questions:

Q. 39 Which of the following numbers is completely divisible by 3?
To check if a number is divisible by 3, sum its digits. If the sum is divisible by 3, the number is divisible by 3.

• (1) 120: Sum of digits = $1 + 2 + 0 = 3$. Since 3 is divisible by 3, 120 is divisible by 3.
• (2) 220: Sum of digits = $2 + 2 + 0 = 4$. Since 4 is not divisible by 3, 220 is not divisible by 3.
• (3)