Exercise 15 Page 5

When multiplying real numbers, the product will be positive if the signs are the same and it will be negative if the signs are different. cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) In our case, there are three positive numbers. We will start by multiplying the first two. They are both positive, so the product will be positive.

Next, we will multiply the new number, 100, by the remaining 10. In this case both numbers are positive, so the product will be positive.

We can check this using a calculator.