This worksheet gives students an opportunity to apply the concepts of addition to add decimals less than 100 with regrouping. In this worksheet, students add decimals by aligning the decimal points and using zero as a placeholder. To find the sum, they must additionally regroup the numbers. In this worksheet, students practice solving problems written in the horizontal format. How numbers are laid out in a problem affects the method a student employs to solve it. Therefore to develop actual fluency and mastery of multiple strategies, students must practice different formats.