Operations with Rational Numbers

Adding Fractions

If there are mixed numbers, turn them into improper fractions.

Get a common denominator.

Add the numerators and keep the denominator the same.

Simplify if you can.

Multiple Choice

$$5\ \frac{2}{3}\ +\frac{2}{6\ }\ =$$   

• $$5\ \frac{4}{9}$$  

• 6

• $$5\ \frac{4}{6}$$  

• $$5\ \frac{4}{9}$$  

Multiple Choice

$$7\ \frac{3}{4\ }\ +\ 2\ \frac{1}{2}\ =$$  

• $$10\ \frac{1}{4}$$  

• $$9\ \frac{3}{4}$$  

• $$10$$  

• $$9\ \frac{4}{6}$$  

Subtracting Fractions

If there are mixed numbers, turn them into improper fractions.

Get a common denominator.

Subtract the numerators and keep the denominator the same.

Simplify if you can.

Multiple Choice

$$\frac{1}{2}-\frac{1}{3}=$$  

• $$\frac{5}{6}$$  

• $$-1$$  

• $$-\frac{1}{3}$$  

• $$\frac{1}{6}$$  

Multiple Choice

$$3\ \frac{2}{3}-1\ \frac{2}{4}=$$  

HARD ONE

• $$\frac{13}{6}$$  

• $$2$$  

• $$\frac{11}{12}$$  

• $$\frac{31}{6}$$  

Multiplying Fractions

If there are mixed numbers, turn them into improper fractions.

Multiply straight across.

Simplify if you can.

Multiple Choice

Simplify if necessary

$$\frac{3}{5}\ \times\ \frac{8}{10}$$  

•   $$\frac{3}{5}$$

•  

  $$\frac{12}{25}$$

•  

  $$\frac{12}{20}$$

•  

  $$\frac{8}{25}$$

Multiple Choice

Simplify if necessary

$$1\frac{1}{3}\ \times2\ \frac{1}{5}$$  

• 6

• $$2\frac{4}{45}$$  

• $$2\frac{13}{15}$$  

• $$2\frac{14}{15}$$  

Dividing Fractions

If there are mixed numbers, turn them into improper fractions.

Keep- Change- Flip

Simplify if you can.

Multiple Choice

¹/₄  ÷  ²/₅

• ⁵/₈
• 2/20
• ¹/₁₀
• ³/₉

Multiple Choice

1/4 ÷ 2 = 

• 8
• 1/8
• 12
• 1/12

Adding and Subtracting Decimals

Line up the decimal.

Multiple Choice

7.9 + 18.72

• 2662
• 26.62
• 1
• 25.62

Multiple Choice

Find the difference
9.73 - 2.52

• 7.22
• 7.23
• 7.21
• 7.34

Multiple Choice

15.07 - 12.2=

• 2.87
• 1.87
• 3.87
• 2.80

Multiple Choice

Add 134.543 + 345.879

• 480.421
• 479.420
• 478.422
• 480.422

Multiply Decimal

Ignore the decimal and multiply like normal.

Add the decimal back in at the end.

Multiple Choice

0.18 x 2.0

• 3.6
• 36
• 0.36
• 0.036

Multiple Choice

What is 0.15 x 0.60?

• 0.09
• 45
• 0.456
• 0.123

Divide Decimal

The first number goes "in the house."

You can not have a decimal "outside the house," so move it over. However many places you move it "outside the house," move it inside as well.

Divide. When you get to the decimal, bring it straight up.

Multiple Choice

Calculate
5.75÷0.25

• 0.23
• 2.3
• 2.03
• 23

Multiple Choice

Calculate
7.8÷0.03

• 2.6
• 26
• 260
• .26