Prior knowledge:

Good understanding of decimal place value
Use a range of number strategies for solving addition and subtraction problems with whole numbers. 

Background:

In this activity students choose an appropriate strategy to solve addition and subtraction problems involving decimals. It is important that students learn to select the most efficient strategy to solve problems.

Comments on the Exercises

Exercise 1
Asks students to solve addition and subtraction problems by rearranging the equation then solving x. Students are not required to know any methods of solving equations to be able to solve these problems. The requirement is that they immediately write the equation in a form that tells them the calculation they need to do (for learning this skill with whole numbers see Task: Strategic Solving Part I.) Students will be required to select an appropriate Add / Sub strategy in order to calculate x.

Exercise 2
Asks students to write word problems for equations in Exercise 1. It could be used as homework.