Their earlier work on basic facts and place value provide the foundation necessary for adding greater numbers. This chapter focuses on addition with addends of up to four digits. Many problems require regrouping more than once. Students must also use the dollar sign and the decimal point in the sum. The valuable skill of estimation is introduced in this chapter.
Estimation is introduced as a strategy for determining reasonable sums.
Analyze problems with too little information to solve In some instances a solution may not be possible simply because not enough information is given. In this chapter if there is enough information, the problems will be solved and if there is not enough information the missing information will be stated. Subtract two-digit numbers Students will subtract numbers with and without regrouping. Their earlier work with basic facts will provide the foundation necessary for making the decision of when and if to regroup. Subtraction skills demand decisions on when and if to regroup.