`\color{#08192D}{|}\color{#102A43}{=}\color{#1F3B73}{****}\color{#2A4D8F}{+}\color{#3A63B8}{**}\color{#4A7EDC}{+}\color{#5AA6FF}{*}\color{#2E6BD3}{o}\color{#3A7FE8}{l}\color{#4693FF}{a}\color{#5AA6FF}{l}\color{#6FB9FF}{a}\color{#82CCFF}{9}\color{#95DFFF}{9}\color{#A8F2FF}{9}\color{#5AA6FF}{*}\color{#4A7EDC}{+}\color{#3A63B8}{**}\color{#2A4D8F}{+}\color{#1F3B73}{***}\color{#102A43}{=}\color{#08192D}{|}`

`7)45(5 4/15 − 4 7/9 − 1 8/45)`

`= 45(79/15 − 43/9 − 53/45)`

`= 45(237/45 − 215/45 − 53/45)`

`= 45(−31/45)`

`= −31`

`8)(7/12 − 1 1/7 + 5/12 + 6/5) : (−5/3)`

`= (7/12 + 5/12 − 8/7 + 6/5) : (−5/3)`

`= (1 − 8/7 + 6/5) : (−5/3)`

`= (−1/7 + 6/5) : (−5/3)`

`= 37/35 : (−5/3)`

`= 37/35 × 3/(−5)`

`= −111/175`

`9)6/13 − 2 2/5 + 7/13 + 21/15 − 37/38`

`= (6/13 + 7/13) − 12/5 + 7/5 − 37/38`

`= 1 − 12/5 + 7/5 − 37/38`

`= 1 − 5/5 − 37/38`

`= −37/38`

`10)−5/8 + 14/18 − 3/8 + 2/9 − 1/2006`

`= (−5/8 − 3/8) + 7/9 + 2/9 − 1/2006`

`= −1 + 1 − 1/2006`

`= −1/2006`