Practice with the help of **Spectrum Math Grade 5 Answer Key Chapter 5 Lesson 5.3 Subtracting Fractions with Unlike Denominators **regularly and improve your accuracy in solving questions.

## Spectrum Math Grade 5 Chapter 5 Lesson 5.3 Subtracting Fractions with Unlike Denominators Answers Key

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

Then, subtract fractions, and write the difference in simplest form.

**Subtract. Write answers in simplest form.**

Question 1.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{3}{4}\) – \(\frac{1}{2}\)

LCD is 4.

\(\frac{3}{4}\) – \(\frac{2}{4}\) = \(\frac{1}{4}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{6}\) – \(\frac{1}{3}\)

LCD is 6

\(\frac{5}{6}\) – \(\frac{2}{6}\) = \(\frac{3}{6}\) = \(\frac{1}{2}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{9}{10}\) – \(\frac{2}{5}\)

LCD is 10

\(\frac{9}{10}\) – \(\frac{4}{10}\) = \(\frac{5}{10}\) = \(\frac{1}{2}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{4}{7}\) – \(\frac{1}{8}\)

LCD is 56

\(\frac{32}{56}\) – \(\frac{7}{56}\) = \(\frac{25}{56}\)

e.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{9}\) – \(\frac{1}{3}\)

LCD is 9

\(\frac{5}{9}\) – \(\frac{1}{3}\) = \(\frac{2}{9}\)

Question 2.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{2}{5}\) – \(\frac{1}{9}\)

LCD is 45.

\(\frac{18}{45}\) – \(\frac{5}{45}\) = \(\frac{13}{45}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{3}{5}\) – \(\frac{2}{7}\)

LCD is 35.

\(\frac{21}{35}\) – \(\frac{10}{35}\) = \(\frac{11}{35}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{2}{3}\) – \(\frac{3}{8}\)

LCD is 24

\(\frac{16}{24}\) – \(\frac{9}{24}\) = \(\frac{7}{24}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{6}\) – \(\frac{1}{3}\)

LCD is 6

\(\frac{5}{6}\) – \(\frac{2}{6}\) = \(\frac{3}{6}\) = \(\frac{1}{2}\)

e.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{3}{4}\) – \(\frac{2}{9}\)

LCD is 36

\(\frac{27}{36}\) – \(\frac{8}{36}\) = \(\frac{19}{36}\)

Question 3.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{7}{10}\) – \(\frac{3}{6}\)

LCD is 30

\(\frac{21}{30}\) – \(\frac{15}{30}\) = \(\frac{6}{30}\) = \(\frac{1}{5}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{8}{9}\) – \(\frac{1}{4}\)

LCD is 36

\(\frac{32}{36}\) – \(\frac{9}{36}\) = \(\frac{23}{36}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{7}{8}\) – \(\frac{5}{12}\)

LCD is 24

\(\frac{21}{24}\) – \(\frac{10}{24}\) = \(\frac{11}{24}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{7}{10}\) – \(\frac{1}{4}\)

LCD is 20

\(\frac{14}{20}\) – \(\frac{5}{20}\) = \(\frac{9}{20}\)

e.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{4}{5}\) – \(\frac{3}{7}\)

LCD is 35

\(\frac{28}{35}\) – \(\frac{15}{35}\) = \(\frac{13}{35}\)

**Subtract. Write answers in simplest form.**

Question 1.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{9}\) – \(\frac{5}{18}\)

LCD is 18

\(\frac{10}{18}\) – \(\frac{5}{18}\) = \(\frac{5}{18}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{8}\) – \(\frac{3}{12}\)

LCD is 24

\(\frac{15}{24}\) – \(\frac{6}{24}\) = \(\frac{9}{24}\) = \(\frac{3}{8}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{7}{18}\) – \(\frac{3}{9}\)

LCD is 18

\(\frac{7}{18}\) – \(\frac{6}{18}\) = \(\frac{1}{18}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{4}{8}\) – \(\frac{7}{16}\)

LCD is 16

\(\frac{8}{16}\) – \(\frac{7}{16}\) = \(\frac{1}{16}\)

Question 2.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{10}\) – \(\frac{1}{15}\)

LCD is 30

\(\frac{15}{30}\) – \(\frac{2}{30}\) = \(\frac{13}{30}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{9}{18}\) – \(\frac{2}{15}\)

LCD is 90

\(\frac{45}{90}\) – \(\frac{12}{90}\) = \(\frac{33}{90}\) = \(\frac{11}{30}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{9}{10}\) – \(\frac{9}{14}\)

LCD is 70

\(\frac{63}{70}\) – \(\frac{45}{70}\) = \(\frac{18}{70}\) = \(\frac{18}{70}\) = \(\frac{9}{35}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{6}{16}\) – \(\frac{1}{8}\)

LCD is 16

\(\frac{6}{16}\) – \(\frac{2}{16}\) = \(\frac{4}{16}\) = \(\frac{1}{4}\)

Question 3.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{8}\) – \(\frac{1}{9}\)

LCD is 72

\(\frac{45}{72}\) – \(\frac{8}{72}\) = \(\frac{37}{72}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{7}{10}\) – \(\frac{7}{15}\)

LCD is 30

\(\frac{21}{30}\) – \(\frac{14}{30}\) = \(\frac{7}{30}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{8}{36}\) – \(\frac{3}{14}\)

LCD is 252

\(\frac{56}{252}\) – \(\frac{54}{252}\) = \(\frac{2}{252}\) = \(\frac{1}{126}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{13}{36}\) – \(\frac{9}{35}\)

LCD is 1260

\(\frac{455}{1260}\) – \(\frac{324}{1260}\) = \(\frac{131}{1260}\)

Question 4.

a.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{10}{25}\) – \(\frac{2}{9}\)

LCD is 225

\(\frac{90}{225}\) – \(\frac{50}{225}\) = \(\frac{40}{225}\) = \(\frac{8}{45}\)

b.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{5}{24}\) – \(\frac{3}{15}\)

LCD is 120

\(\frac{25}{120}\) – \(\frac{24}{120}\) = \(\frac{1}{120}\)

c.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{1}{8}\) – \(\frac{3}{26}\)

LCD is 104

\(\frac{13}{104}\) – \(\frac{12}{104}\) = \(\frac{1}{104}\)

d.

Answer:

When subtracting fractions that have different denominators, rename fractions to have a common denominator.

\(\frac{9}{14}\) – \(\frac{1}{8}\)

LCD is 56

\(\frac{36}{104}\) – \(\frac{7}{56}\) = \(\frac{29}{56}\)