Question

lesson 9-5
additional practice
name

review
you can subtract fractions with unlike denominators by
finding a common multiple of the denominators to use as a
common denominator.
ollies math notebook weighs $\frac{3}{8}$ pound. his science notebook
weighs $\frac{1}{6}$ pound. how much more does ollies math notebook
weigh than his science notebook?
to solve, find $\frac{3}{8} - \frac{1}{6}$.
for the denominators 8 and 6, a common multiple is 24. write
equivalent fractions using 24 as the denominator.
$\frac{3}{8} × \frac{3}{3} = \frac{9}{24}$ $\frac{1}{6} × \frac{4}{4} = \frac{24}{24}$
$\frac{3}{8} - \frac{1}{6} = \frac{9}{24} - \frac{4}{24} = \frac{5}{24}$
ollies math notebook weighs $\frac{5}{24}$ pound more than his
science notebook.

find the difference. show your work.

1. $\frac{1}{3} - \frac{1}{6} =$
2. $\frac{2}{3} - \frac{1}{5} =$
3. $\frac{4}{9} - \frac{1}{6} =$
4. $\frac{3}{4} - \frac{1}{6} =$
5. $\frac{7}{10} - \frac{1}{4} =$
6. $\frac{2}{3} - \frac{1}{4} =$

student practice book
97

Explanation:

Step1: Find common denominator (6)

$\frac{1}{3} = \frac{1\times2}{3\times2} = \frac{2}{6}$

Step2: Subtract the fractions

$\frac{2}{6} - \frac{1}{6} = \frac{1}{6}$

---

Step1: Find common denominator (15)

$\frac{2}{3} = \frac{2\times5}{3\times5} = \frac{10}{15}$, $\frac{1}{5} = \frac{1\times3}{5\times3} = \frac{3}{15}$

Step2: Subtract the fractions

$\frac{10}{15} - \frac{3}{15} = \frac{7}{15}$

---

Step1: Find common denominator (18)

$\frac{4}{9} = \frac{4\times2}{9\times2} = \frac{8}{18}$, $\frac{1}{6} = \frac{1\times3}{6\times3} = \frac{3}{18}$

Step2: Subtract the fractions

$\frac{8}{18} - \frac{3}{18} = \frac{5}{18}$

---

Step1: Find common denominator (12)

$\frac{3}{4} = \frac{3\times3}{4\times3} = \frac{9}{12}$, $\frac{1}{6} = \frac{1\times2}{6\times2} = \frac{2}{12}$

Step2: Subtract the fractions

$\frac{9}{12} - \frac{2}{12} = \frac{7}{12}$

---

Step1: Find common denominator (20)

$\frac{7}{10} = \frac{7\times2}{10\times2} = \frac{14}{20}$, $\frac{1}{4} = \frac{1\times5}{4\times5} = \frac{5}{20}$

Step2: Subtract the fractions

$\frac{14}{20} - \frac{5}{20} = \frac{9}{20}$

---

Step1: Find common denominator (12)

$\frac{2}{3} = \frac{2\times4}{3\times4} = \frac{8}{12}$, $\frac{1}{4} = \frac{1\times3}{4\times3} = \frac{3}{12}$

Step2: Subtract the fractions

$\frac{8}{12} - \frac{3}{12} = \frac{5}{12}$

Answer:

1. $\frac{1}{6}$
2. $\frac{7}{15}$
3. $\frac{5}{18}$
4. $\frac{7}{12}$
5. $\frac{9}{20}$
6. $\frac{5}{12}$