4.1 Adding and Subtracting Fractions

What is the sum of these fractions?

• 4/5
• 3/20
• 17/20
• 4/20

• 14/16
• 7/8
• 8/7
• 4/10

• - 3/56
• 18/56
• - 4/15
• 29/56

• 1/12
• 1
• 2/35
• 23/25

Is this a correct answer?

• Yes, the student correctly added.
• No, you cannot add unlike denominators
• No, 5 + 7 is not 12
• No, 2 + 3 is not 5

What is the first step in solving this problem? 
⅘ + ½ =

• Add the top parts of the fraction
• Rewrite the fractions in the simplest form. 
• Find a common denominator. 
• Make each fraction into an improper faction. 

8/9 - 1/3 = 

• 7/6
• 5/9
• 2/3
• 8/27

A contractor was paving a driveway. He mixed 4/7 ton of sand and 1/3 ton of concrete. How much did the mixture weigh?

• 1/4 ton
• 2/5 ton
• 5/7 ton
• 19/21 ton

What is the first step in solving this problem? 
⅘ + ½ =

• Add the top parts of the fraction
• Rewrite the fractions in the simplest form. 
• Find a common denominator. 
• Make each fraction into an improper faction. 

What must you have to add and subtract fractions?

• Common numerators
• Different numerators
• Different denominators
• Common denominators