Adding and Subtracting Mixed Numbers with Unlike Denominators

What is the first step in the four square method for adding and subtracting mixed numbers with unlike fractions?

• Write the problem

• Multiply the numerators

• Simplify the fractions

• Find the least common denominator

How do you find the least common denominator (LCD) for the fractions 3/4 and 1/3?

• Multiply the denominators

• Find the greatest common factor

• List the multiples of each denominator and find the smallest common multiple

• Add the denominators

What is the least common denominator (LCD) of 3/4 and 1/3?

• 12

• 9

• 6

• 15

When rewriting the problem with the new denominator, what must you do to the numerator?

• Divide the numerator by the same number you multiplied the denominator

• Subtract the same number from the numerator

• Multiply the numerator by the same number you multiplied the denominator

• Add the same number to the numerator

In the example problem, what is the least common denominator (LCD) for the fractions 3/4 and 1/8?

• 16

• 24

• 12

• 8

What do you do if you don't have enough in terms of your fraction to subtract?

• Divide the denominator

• Multiply the numerator

• Borrow from the whole number

• Add more to the numerator

What is the final simplified answer for 3 and 3/4 minus 1 and 7/8?

• 1 and 1/8

• 1 and 3/8

• 1 and 7/8

• 1 and 5/8

What is the least common denominator (LCD) for the fractions 1/5 and 2/2?

• 5

• 10

• 15

• 20

What is the final simplified answer for 2 and 1/5 plus 8 and 2/2?

• 10 and 9/10

• 10 and 1/5

• 10 and 2/5

• 10 and 7/10

What should you do if the greatest common factor of the numerator and denominator is 1?

• Divide both by 2

• Add 1 to both

• Multiply both by 2

• Leave it as it is