In this Grade 7 Saxon Math Course 2 lesson, students learn how to add and subtract mixed measures — measurements that combine different units from the same category, such as yards, feet, and inches or hours, minutes, and seconds. The lesson covers aligning like units, simplifying results by converting between units, and borrowing across units when subtracting requires regrouping.
Section 1
📘 Adding and Subtracting Mixed Measures
A mixed measure is a measurement that includes different units from the same category. To add or subtract, align like units and then regroup when necessary.
This is the foundation. Next, you’ll see worked examples for adding and subtracting mixed measures, including problems that require regrouping across different units.
Section 2
Mixed Measure
A mixed measure is a measurement that includes different units from the same category, like length or time.
5 ft 10 in.10 lb 8 oz.3 weeks 4 days.Think of it as a measurement combo meal! Instead of just saying a movie is 108 minutes, we say it's 1 hour and 48 minutes, mixing bigger and smaller units. This makes measurements easier to understand at a glance, combining different units for a more practical description.
Section 3
Adding Mixed Measures
To add mixed measures, align the numbers to add the same units. Then, simplify the result when possible.
1 yd 2 ft 9 in. + 2 yd 1 ft 5 in. = 3 yd 3 ft 14 in., which simplifies to 4 yd 1 ft 2 in.2 hr 30 min 40 s + 1 hr 40 min 35 s = 3 hr 70 min 75 s, which simplifies to 4 hr 11 min 15 s.It’s like normal addition with a fun extra step! First, add each column of units together. Then, starting from the smallest unit on the right, simplify any large amounts by converting them into the next larger unit (like turning 70 seconds into 1 minute and 10 seconds).
Section 4
Subtracting Mixed Measures
When subtracting mixed measures, it is often necessary to convert units before you can subtract.
5 days 10 hr - 2 days 15 hr, first borrow 1 day: 4 days 34 hr - 2 days 15 hr = 2 days 19 hr.4 yd 5 in. - 1 yd 1 ft 8 in., first borrow 1 yard, then 1 foot: 3 yd 2 ft 17 in. - 1 yd 1 ft 8 in. = 2 yd 1 ft 9 in.Subtraction can get tricky when you need to subtract a larger number from a smaller one. The secret is to 'borrow' from the bigger unit to the left, converting it into smaller pieces (like 1 hour becomes 60 minutes). This gives you enough to subtract easily across all units.
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Section 1
📘 Adding and Subtracting Mixed Measures
A mixed measure is a measurement that includes different units from the same category. To add or subtract, align like units and then regroup when necessary.
This is the foundation. Next, you’ll see worked examples for adding and subtracting mixed measures, including problems that require regrouping across different units.
Section 2
Mixed Measure
A mixed measure is a measurement that includes different units from the same category, like length or time.
5 ft 10 in.10 lb 8 oz.3 weeks 4 days.Think of it as a measurement combo meal! Instead of just saying a movie is 108 minutes, we say it's 1 hour and 48 minutes, mixing bigger and smaller units. This makes measurements easier to understand at a glance, combining different units for a more practical description.
Section 3
Adding Mixed Measures
To add mixed measures, align the numbers to add the same units. Then, simplify the result when possible.
1 yd 2 ft 9 in. + 2 yd 1 ft 5 in. = 3 yd 3 ft 14 in., which simplifies to 4 yd 1 ft 2 in.2 hr 30 min 40 s + 1 hr 40 min 35 s = 3 hr 70 min 75 s, which simplifies to 4 hr 11 min 15 s.It’s like normal addition with a fun extra step! First, add each column of units together. Then, starting from the smallest unit on the right, simplify any large amounts by converting them into the next larger unit (like turning 70 seconds into 1 minute and 10 seconds).
Section 4
Subtracting Mixed Measures
When subtracting mixed measures, it is often necessary to convert units before you can subtract.
5 days 10 hr - 2 days 15 hr, first borrow 1 day: 4 days 34 hr - 2 days 15 hr = 2 days 19 hr.4 yd 5 in. - 1 yd 1 ft 8 in., first borrow 1 yard, then 1 foot: 3 yd 2 ft 17 in. - 1 yd 1 ft 8 in. = 2 yd 1 ft 9 in.Subtraction can get tricky when you need to subtract a larger number from a smaller one. The secret is to 'borrow' from the bigger unit to the left, converting it into smaller pieces (like 1 hour becomes 60 minutes). This gives you enough to subtract easily across all units.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter