## Problem

fill appropriate numbers in the following parentheses.Â

## Analysis

In equation (1), since the tens digit of the three-digit number multiplied by 4 results in 4, it means the units digit of the three-digit number multiplied by 4 cannot carry over. From this, we can deduce that the units digit of the three-digit number might be 0, 1, or 2. In equation (2), since the tens digit of the product is 5 and the tens digit 1 of the three-digit number multiplied by 4 results in 5, we know the units digit of the three-digit number multiplied by 4 gives a product that carries over to the tens digit, and it carries over by 1. This means the product of the units digit of the three-digit number and 4 is in the teens. From this, we can deduce that the units digit of the three-digit number might be 3 or 4.

## Solutions

(1) can be

(2) can be