Exercise 12 Page 49

When multiply real numbers, the product of an integer a by an integer b is always positive if those integers have the same sign. cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) We want to find the given product. - 0.6 * (- 0.62) In this case both numbers are negative, so the product will be positive. Before evaluate this expression, we will rewrite the decimal numbers as fractions. We will write fractions with 1 in the denominator.

- 0.6 * (- 0.62)

NumberToFrac

a = 1* a/1

- 0.6 * 1/1 * - 0.62 * 1/1

MultByOne

a * 1=a

- 0.6/1 * - 0.62/1

The calculations are easier if we multiply the divisor and the dividend by the same power of 10 so that the divisor is a whole number. In this case, we will multiply by 10 the numerator and denominator of - 0.61 and by 100 the numerator and denominator of - 0.621.

- 0.6/1 * - 0.62/1

ExpandFrac

a/b=a * 10/b * 10

- 0.6 * 10/1 * 10 * - 0.62/1

ExpandFrac

a/b=a * 100/b * 100

- 0.6 * 10/1 * 10* - 0.62* 100/1 * 100

Multiply

- 6/10 * - 62/100

Now that we have the fractions, we can evaluate the product. When we multiply fractions, we need to remember that the product of two fractions is equal to the product of the numerators divided by the product of the denominators. Let's find the given product!

- 6/10 * - 62/100

MultFrac

Multiply fractions

- 6* - 62/10* 100

MultNegNegOnePar

- a(- b)=a* b

6* 62/10* 100

Multiply

372/1000

ReduceFrac

a/b=.a / 4./.b / 4.

372/ 4/1000/ 4