Add Two 3-Digit Numbers without Regrouping: Missing Numbers Worksheet

Students use the count on strategy or the relationship between addition and subtraction to find the missing number in this worksheet. However, they do not need to regroup numbers to get to the answer in add two 3-digit numbers without regrouping worksheet. In each problem, the numbers are laid out in the horizontal format. Students should try to use different strategies involving composing and decomposing numbers to solve these problems. This will help them develop flexibility and fluency.