In this pre-algebra or 7th grade math lesson, we first use the number line to solve some fraction addition & subtraction problems that involve negative fractions.
Then, we solve decimal additions & subtractions, again, involving negative decimals. They are solved using the same principles as in integer addition and subtraction.
Lastly, I explain a money-related problem that involves positive and negative decimals (money amounts), in the context of a bank account balance.
The focus of the lesson is adding and subtracting rational numbers (fractions & decimals).
In the 2nd part of the lesson, we continue with adding and subtracting negative fractions. It's NOT difficult at all! We simply find the common denominator, and after that, we have an integer addition or subtraction in the numerator.
We also practice finding the DISTANCE between a negative and a positive integer, or between two negative rational numbers -- a number line helps here!
Math Mammoth Rational Numbers — a short workbook where you can find worksheets to match this lesson.
Math Mammoth Grade 7 curriculum (pre-algebra)
Back to rational numbers videos index
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