Addition, Subtraction, Multiplication and Division - Subtracting Whole Numbers with more than 4-digits - Presentation

The lesson on subtracting whole numbers with more than four digits provides students with a comprehensive understanding of the subtraction process. It begins with a discussion about what it means to subtract numbers larger than four digits, followed by a series of activities designed to practice and reinforce this skill. The first activity asks students to consider whether they will need to exchange (borrow) when subtracting multi-digit numbers, using examples such as 4,648 minus 2,347. This activity is accompanied by a visual representation of the place value columns, which helps students understand the concept of exchanging across different place values.

Further activities involve real-world scenarios, such as calculating how much a plane descends during a flight by subtracting the descent from the original altitude. This contextual approach helps students grasp the practical applications of subtraction in everyday situations. For example, one problem asks students to determine the new altitude after a plane descends 8,896 feet and then another 989 feet from an initial altitude of 29,456 feet. The lesson continues with a variety of subtraction problems, including determining the remaining balance of a business account after making purchases and comparing annual earnings between individuals to find out who earns more. These activities underscore the importance of starting with the ones column when subtracting and consider the potential issues that could arise if the correct order is not followed or if numbers with different digit lengths are not aligned properly.