9G (2.5) Operations with fractions

(2.5)
(Operations with fractions)

Adding fractions.
You can do this in your calculator but it's important to know what's happening

Multiple Choice

Make the following fractions have the same bottom.

$$\frac{3}{4}+\frac{5}{2}=?$$

• $$\frac{\left(2\right)3}{\left(2\right)4}+\frac{\left(4\right)5}{\left(4\right)2}=\frac{6}{8}+\frac{20}{8}=\frac{26}{8}$$

• $$\frac{8}{6}$$

Multiple Choice

Make the following fractions have the same bottom.

$$\frac{8}{3}+\frac{8}{5}=?$$

• $$\frac{\left(5\right)8}{\left(5\right)3}+\frac{\left(3\right)8}{\left(3\right)5}=\frac{40}{15}+\frac{24}{15}=\frac{64}{15}$$

• $$\frac{16}{8}$$

Multiple Choice

Make the following fractions have the same bottom.

$$\frac{10}{7}+\frac{1}{8}=?$$

• $$\frac{10\cdot8}{7\cdot8}+\frac{1\cdot7}{8\cdot7}=\frac{87}{56}$$

• $$\frac{11}{15}$$

• $$\frac{13}{10}+\frac{2}{10}$$

• $$\frac{70}{49}$$

• $$\frac{10\cdot7}{7\cdot7}+\frac{1\cdot8}{8\cdot8}=\frac{78}{113}$$

Multiple Choice

Make the following fractions have the same bottom.

$$\frac{14}{4}+\frac{9}{10}=?$$

• $$\frac{14\cdot10}{4\cdot10}+\frac{9\cdot4}{10\cdot4}=\frac{176}{40}$$

• $$\frac{11}{15}$$

• $$\frac{24}{19}+\frac{18}{19}$$

• $$\frac{70}{49}$$

• $$\frac{14\cdot4}{4\cdot4}+\frac{9\cdot10}{10\cdot10}=\frac{240}{116}$$

Multiplying fractions by an integer

Multiple Choice

$$\frac{4}{9}\cdot5\ =\ ?$$

• $$\frac{4}{9}\cdot\frac{5}{1}=\frac{20}{9}$$

• $$\frac{20}{45}$$

Multiple Choice

$$\frac{13}{7}\cdot2\ =\ ?$$

• $$\frac{13}{7}\cdot\frac{2}{1}=\frac{26}{7}$$

• $$\frac{26}{14}$$

Multiple Choice

$$\frac{21}{19}\cdot3\ =\ ?$$

• $$\frac{21}{19}\cdot\frac{3}{1}=\frac{63}{19}$$

• $$\frac{63}{57}$$

Multiplying fractions by fractions

Multiple Choice

$$\frac{4}{7}\cdot\frac{2}{3}=\ ?$$

• $$\frac{4\cdot2}{7\cdot3}=\frac{8}{21}$$

• $$\frac{6}{10}$$

Multiple Choice

$$\frac{7}{10}\cdot\frac{7}{10}=\ ?$$

• $$\frac{7\cdot7}{10\cdot10}=\frac{49}{100}$$

• $$\frac{14}{20}$$

Multiple Choice

$$\frac{11}{5}\cdot\frac{19}{2}=\ ?$$

• $$\frac{11\cdot19}{5\cdot2}=\frac{209}{10}$$

• $$\frac{30}{7}$$

Dividing fractions by an integer

Multiple Choice

$$\frac{\frac{4}{5}}{7}=\ ?$$

• $$\frac{4}{\frac{5}{7}}=\frac{4}{5}\cdot\frac{1}{7}=\frac{4}{35}$$

• $$\frac{\left(\frac{4}{7}\right)}{\left(\frac{5}{7}\right)}$$

Multiple Choice

$$\frac{\frac{9}{11}}{3}=\ ?$$

• $$\frac{9}{\frac{11}{3}}=\frac{9}{11}\cdot\frac{1}{3}=\frac{9}{33}$$

• $$\frac{\left(\frac{9}{3}\right)}{\left(\frac{11}{3}\right)}$$

Multiple Choice

$$\frac{\frac{3}{4}}{11}=\ ?$$

• $$\frac{3}{4}\cdot\frac{1}{11}=\frac{3}{44}$$

• $$\frac{\left(\frac{3}{11}\right)}{\left(\frac{4}{11}\right)}$$

• $$\frac{3}{4}\cdot11=\frac{33}{4}$$

Multiple Choice

$$\frac{\frac{5}{13}}{3}=\ ?$$

• $$\frac{5}{13}\cdot\frac{1}{3}=\frac{5}{39}$$

• $$\frac{\left(\frac{5}{3}\right)}{\left(\frac{13}{3}\right)}$$

• $$\frac{5}{13}\cdot3=\frac{15}{13}$$

Dividing fractions by fractions

Multiple Choice

$$\frac{\frac{9}{11}}{\frac{8}{7}}=\ ?$$

• $$\frac{9}{\frac{11}{\frac{8}{7}}}=\frac{9}{11}\cdot\frac{7}{8}=\frac{63}{88}$$

• 0

You flip the bottom fraction and multiply it

Multiple Choice

$$\frac{\frac{4}{5}}{\frac{1}{9}}=\ ?$$

• $$\frac{\frac{4}{5}}{\frac{1}{9}}=\frac{4}{5}\cdot\frac{1}{9}=\frac{4}{45}$$

• $$\frac{\frac{4}{9}}{\frac{5}{9}}$$

Multiple Choice

$$\frac{\frac{1}{7}}{\frac{2}{11}}=\ ?$$

• $$\frac{1}{7}\cdot\frac{2}{11}=\frac{2}{77}$$

• $$\frac{\frac{2}{11}}{\frac{14}{11}}$$

• $$\frac{1}{7}\cdot\frac{11}{2}=\frac{11}{14}$$

Multiple Choice

$$\frac{\frac{5}{13}}{\frac{4}{7}}=\ ?$$

• $$\frac{5}{13}\cdot\frac{4}{7}=\frac{20}{91}$$

• $$\frac{\frac{2}{11}}{\frac{14}{11}}$$

• $$\frac{5}{13}\cdot\frac{7}{4}=\frac{35}{52}$$

Multiple Choice

$$\frac{\frac{1}{3}}{\frac{2}{5}}=\ ?$$

• $$\frac{6}{5}$$

• $$\frac{2}{15}$$

• $$\frac{\frac{2}{5}}{\frac{6}{5}}$$

• $$\frac{10}{30}$$

The End