Adding Signed Numbers · Deep Dive 5

ElleMath-speak

In this lesson, we add signed numbers. Signed numbers are positive and negative numbers, including fractions and decimals.

FinnPlain English

Think of it as money. Positive numbers are money you have. Negative numbers are money you owe. The answer is your net worth: what you have left after you pay off everything you owe.

ElleMath-speak

Before you add, rewrite every subtraction as addition of the opposite.

FinnPlain English

Change every minus sign to plus the opposite. Then the whole problem is adding, and adding is just counting up your money and your debts.

Write it down. Do every change on paper, one line per step. Changing signs in your head is the number one reason for missed problems. If you changed something, it should be on the paper.

Go in order. Each tile has a short explanation, then a "Let me try a few" button.

1Money You Have, Money You OweSigned numbers, opposites, and net worthStart here 2Adding Signed NumbersPay off what you can. What's left is the answer. 3Subtraction? Add the OppositeChange it, then add 4Fractions, Decimals, and Mixed NumbersParts of a dollar work the same way 5Distance and Real-World ProblemsHow far apart, and how much it changed

When you have finished

At the end of each tile you will find a review form to give us feedback.

NC standard: NC.7.NS.1.

Where this goes next

Previous lesson: Circle GraphsReading percents from a pie. Next lesson: Subtracting Signed NumbersSubtracting means adding the opposite. Back to the Math 7 mapEvery 7th grade lesson, in course order.