Exercise 13 Page 49

We want to find the given product. - 0.2 * - 56 We will start by rewriting the decimal number as a fraction. To do so, we can start by writing a fraction with 1 in the denominator. 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 0.21.

- 0.2/1 * (- 5/6)

MoveNegFracToNum

Put minus sign in numerator

- 0.2/1 * - 5/6

ExpandFrac

a/b=a * 10/b * 10

- 0.2 * 10/1 * 10 * -5/6

Multiply

Multiply

- 2/10 * - 5/6

Now that we have the fractions, we can evaluate the product. 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 (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) In our case both are negative, so the product will be positive. 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 product!

- 2/10 * - 5/6

MultFrac

Multiply fractions

- 2* (- 5)/10* 6

MultNegNegOnePar

- a(- b)=a* b

2* 5/10* 6

Multiply

Multiply

10/60

ReduceFrac

a/b=.a / 5./.b / 5.

10/ 10/60/ 10

CalcQuot

Calculate quotient

1/6