SiriusLesson 3 Multiplying and dividing Rational numbers

Multiplying and Dividing Rational Numbers

Sirius Lesson 3
STAAR Review

Open Ended

Give me an example of a rational number.

Multiplying Fractions

Open Ended

How can we multiply fractions and mixed numbers?

Open Ended

How do we multiply a whole number by a fraction?

Dividing fractions

Keep Change Flip

To divide fractions, we multiply by the fractions reciprocal.

Multiplying Decimals

Key Things to Remember

• Start multiplying with the right digit of the second factor. At each step, move one place to the left.

• Disregard decimal points when you multiply.

• The number of decimal places in the product is the total nubmer of decimal places in the original factors.

​So, 2.7 ⋅ 0.384 =1.0368

Open Ended

How do you divide a fraction by a decimal?

Multiple Choice

One gallon of orange juice costs $3.40. The Javier family drank 2/5 of a gallon of orange juice this morning. What is the cost of the orange juice they drank?

• $2.04

• $8.50

• $1.36

• Not here