5.

`a) $\frac{2}{10}$ + $\frac{5}{10}$ = $\frac{7}{10}$`

`b) $\frac{1}{2}$ + $\frac{3}{4}$ = $\frac{2}{4}$ + $\frac{3}{4}$ = $\frac{5}{4}$`

`c) $\frac{2}{3}$ - $\frac{1}{15}$ = $\frac{10}{15}$ - $\frac{1}{15}$ = $\frac{9}{15}$ = $\frac{3}{5}$`

`d) 1 - $\frac{1}{100}$ = $\frac{100}{100}$ - $\frac{1}{100}$ = $\frac{99}{100}$`

`e) 3 - $\frac{3}{5}$ = $\frac{15-3}{5}$ = $\frac{12}{5}$`

`g) $\frac{3}{5}$ + 1 = $\frac{3+5}{5}$ = $\frac{8}{5}$`

6. 

`a) $\frac{2}{5}$ + $\frac{2}{3}$ + $\frac{3}{4}$ = $\frac{24+40+45}{60}$ = $\frac{109}{60}$`

`b) $\frac{4}{3}$ - $\frac{5}{2}$ + $\frac{5}{6}$ = $\frac{8-15+5}{6}$ = $\frac{-2}{6}$ = $\frac{-1}{3}$`

`c) $\frac{1}{6}$ : $\frac{5}{24}$ × $\frac{2}{3}$ = $\frac{1}{6}$ × $\frac{24}{5}$ × $\frac{2}{3}$ = $\frac{4}{45}$`

`d) $\frac{4}{7}$ + $\frac{2}{5}$ × 2 = $\frac{20}{35}$ + $\frac{28}{35}$ = $\frac{48}{35}$`

7. 

`a) $\frac{2}{3}$ × $\frac{5}{4}$ = $\frac{5}{6}$`

`b) 4 × $\frac{3}{8}$ = $\frac{3}{2}$`

`c) $\frac{7}{8}$ × 6 = $\frac{21}{4}$`

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