PreCalculus worksheet featuring fraction operations and algebraic simplification exercises.
PreCalculus worksheet with fractions exercises, including evaluation and simplification problems involving positive and negative fractions, mixed numbers, and algebraic expressions.
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Step-by-step solution for: Precalculus - Fractions Worksheet
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Show Answer Key & Explanations
Step-by-step solution for: Precalculus - Fractions Worksheet
Let's solve each problem step by step from the Precalculus Fractions Worksheet. We'll evaluate and simplify expressions involving fractions, integers, and algebraic terms.
---
We will evaluate each expression using fraction arithmetic rules (common denominators, signs, etc.).
---
#### 1) $\left(-\frac{1}{6}\right) - \frac{2}{5}$
Find a common denominator: $30$
$$
= \left(-\frac{5}{30}\right) - \frac{12}{30} = -\frac{17}{30}
$$
✔ Answer: $-\frac{17}{30}$
---
#### 2) $(-2\frac{1}{2}) + 2\frac{2}{3}$
Convert to improper fractions:
- $-2\frac{1}{2} = -\frac{5}{2}$
- $2\frac{2}{3} = \frac{8}{3}$
Common denominator: 6
$$
= -\frac{15}{6} + \frac{16}{6} = \frac{1}{6}
$$
✔ Answer: $\frac{1}{6}$
---
#### 3) $\left(-\frac{1}{4}\right) - 1\frac{1}{3}$
Convert mixed number: $1\frac{1}{3} = \frac{4}{3}$
So:
$$
= -\frac{1}{4} - \frac{4}{3}
$$
Common denominator: 12
$$
= -\frac{3}{12} - \frac{16}{12} = -\frac{19}{12}
$$
Or as mixed number: $-1\frac{7}{12}$
✔ Answer: $-\frac{19}{12}$ or $-1\frac{7}{12}$
---
#### 4) $\left(-\frac{1}{4}\right) - \left(-\frac{3}{8}\right)$
Subtracting a negative is adding:
$$
= -\frac{1}{4} + \frac{3}{8}
$$
Common denominator: 8
$$
= -\frac{2}{8} + \frac{3}{8} = \frac{1}{8}
$$
✔ Answer: $\frac{1}{8}$
---
#### 5) $\frac{13}{8} - 1\frac{1}{3}$
Convert $1\frac{1}{3} = \frac{4}{3}$
Now:
$$
= \frac{13}{8} - \frac{4}{3}
$$
LCM of 8 and 3 is 24:
$$
= \frac{39}{24} - \frac{32}{24} = \frac{7}{24}
$$
✔ Answer: $\frac{7}{24}$
---
#### 6) $\left(-\frac{1}{2}\right) + \left(-\frac{7}{8}\right)$
Same sign → add absolute values, keep negative:
$$
= -\left(\frac{1}{2} + \frac{7}{8}\right) = -\left(\frac{4}{8} + \frac{7}{8}\right) = -\frac{11}{8}
$$
Or: $-1\frac{3}{8}$
✔ Answer: $-\frac{11}{8}$
---
#### 7) $\frac{5}{7} + \left(-\frac{9}{5}\right)$
$$
= \frac{5}{7} - \frac{9}{5}
$$
LCM of 7 and 5 is 35:
$$
= \frac{25}{35} - \frac{63}{35} = -\frac{38}{35}
$$
Or: $-1\frac{3}{35}$
✔ Answer: $-\frac{38}{35}$
---
#### 8) $(-2) + 3\frac{1}{2}$
Convert: $3\frac{1}{2} = \frac{7}{2}$
$$
= -2 + \frac{7}{2} = -\frac{4}{2} + \frac{7}{2} = \frac{3}{2}
$$
Or: $1\frac{1}{2}$
✔ Answer: $\frac{3}{2}$
---
#### 9) $(-2) - \frac{3}{2}$
$$
= -2 - \frac{3}{2} = -\frac{4}{2} - \frac{3}{2} = -\frac{7}{2}
$$
Or: $-3\frac{1}{2}$
✔ Answer: $-\frac{7}{2}$
---
#### 10) $(-1) - \left(-3\frac{1}{4}\right)$
Subtracting a negative → add:
$$
= -1 + 3\frac{1}{4} = -1 + \frac{13}{4} = -\frac{4}{4} + \frac{13}{4} = \frac{9}{4}
$$
Or: $2\frac{1}{4}$
✔ Answer: $\frac{9}{4}$
---
#### 11) $\left(-\frac{2}{8}\right) + 3\frac{1}{2} - \frac{3}{4}$
Simplify $-\frac{2}{8} = -\frac{1}{4}$
$3\frac{1}{2} = \frac{7}{2}$
Now:
$$
= -\frac{1}{4} + \frac{7}{2} - \frac{3}{4}
$$
Convert all to fourths:
$$
= -\frac{1}{4} + \frac{14}{4} - \frac{3}{4} = \frac{10}{4} = \frac{5}{2}
$$
Or: $2\frac{1}{2}$
✔ Answer: $\frac{5}{2}$
---
#### 12) $\frac{3}{4} - \frac{7}{6} - 2$
Convert to common denominator (LCM of 4, 6, 1 is 12):
$$
= \frac{9}{12} - \frac{14}{12} - \frac{24}{12} = \frac{9 - 14 - 24}{12} = \frac{-29}{12}
$$
Or: $-2\frac{5}{12}$
✔ Answer: $-\frac{29}{12}$
---
#### 13) $\left(-\frac{3}{4}\right) + \frac{2}{3} + 3 - 1\frac{6}{7}$
Convert all to improper fractions where needed:
- $3 = \frac{3}{1}$
- $1\frac{6}{7} = \frac{13}{7}$
So:
$$
= -\frac{3}{4} + \frac{2}{3} + \frac{3}{1} - \frac{13}{7}
$$
Find LCM of 4, 3, 1, 7 → 84
Convert each:
- $-\frac{3}{4} = -\frac{63}{84}$
- $\frac{2}{3} = \frac{56}{84}$
- $\frac{3}{1} = \frac{252}{84}$
- $-\frac{13}{7} = -\frac{156}{84}$
Add:
$$
= -63 + 56 + 252 - 156 = (-63 + 56) = -7; (252 - 156) = 96 → -7 + 96 = 89
$$
So: $\frac{89}{84}$
Or: $1\frac{5}{84}$
✔ Answer: $\frac{89}{84}$
---
#### 14) $\left(-\frac{3}{2}\right) - 4\left(-2\right) - 4\frac{2}{3}$
First: $-4(-2) = +8$
$4\frac{2}{3} = \frac{14}{3}$
So:
$$
= -\frac{3}{2} + 8 - \frac{14}{3}
$$
Convert to common denominator (LCM of 2,1,3 is 6)
- $-\frac{3}{2} = -\frac{9}{6}$
- $8 = \frac{48}{6}$
- $-\frac{14}{3} = -\frac{28}{6}$
Now:
$$
= -\frac{9}{6} + \frac{48}{6} - \frac{28}{6} = \frac{11}{6}
$$
Or: $1\frac{5}{6}$
✔ Answer: $\frac{11}{6}$
---
#### 15) $1 + \frac{9}{5} + 3\frac{1}{6} + \left(-3\frac{1}{2}\right)$
Convert all:
- $1 = 1$
- $\frac{9}{5} = \frac{9}{5}$
- $3\frac{1}{6} = \frac{19}{6}$
- $-3\frac{1}{2} = -\frac{7}{2}$
Now:
$$
= 1 + \frac{9}{5} + \frac{19}{6} - \frac{7}{2}
$$
LCM of 1,5,6,2 → 30
Convert:
- $1 = \frac{30}{30}$
- $\frac{9}{5} = \frac{54}{30}$
- $\frac{19}{6} = \frac{95}{30}$
- $-\frac{7}{2} = -\frac{105}{30}$
Add:
$$
= \frac{30 + 54 + 95 - 105}{30} = \frac{74}{30} = \frac{37}{15}
$$
Or: $2\frac{7}{15}$
✔ Answer: $\frac{37}{15}$
---
#### 16) $\left(-\frac{2}{3}\right) - \left(-\frac{1}{3}\right) + 2 - \left(-\frac{9}{7}\right)$
Simplify negatives:
- $-\left(-\frac{1}{3}\right) = +\frac{1}{3}$
- $-\left(-\frac{9}{7}\right) = +\frac{9}{7}$
So:
$$
= -\frac{2}{3} + \frac{1}{3} + 2 + \frac{9}{7}
$$
Combine like terms:
- $-\frac{2}{3} + \frac{1}{3} = -\frac{1}{3}$
Now:
$$
= -\frac{1}{3} + 2 + \frac{9}{7}
$$
Convert to common denominator (LCM of 3,1,7 = 21)
- $-\frac{1}{3} = -\frac{7}{21}$
- $2 = \frac{42}{21}$
- $\frac{9}{7} = \frac{27}{21}$
Add:
$$
= -\frac{7}{21} + \frac{42}{21} + \frac{27}{21} = \frac{62}{21}
$$
Or: $2\frac{20}{21}$
✔ Answer: $\frac{62}{21}$
---
These are algebraic expressions with variables. Combine like terms.
---
#### 17) $\left(-\frac{3}{2}x - 1\right) + \left(-\frac{5}{3}x^2 + \frac{4}{3}\right)$
Group like terms:
- $-\frac{5}{3}x^2$
- $-\frac{3}{2}x$
- $-1 + \frac{4}{3} = \frac{-3 + 4}{3} = \frac{1}{3}$
So:
$$
= -\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}
$$
✔ Answer: $-\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}$
---
#### 18) $\left(\frac{14}{3} - \frac{1}{2}\right) + \left(\frac{7}{2}x + \frac{4}{3}x^2\right)$
First: $\frac{14}{3} - \frac{1}{2}$
LCM = 6:
$$
= \frac{28}{6} - \frac{3}{6} = \frac{25}{6}
$$
Then: $\frac{7}{2}x + \frac{4}{3}x^2$
So combine:
$$
= \frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}
$$
✔ Answer: $\frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}$
---
#### 19) $\left(\frac{12}{6}x^3 + \frac{2}{3}\right) + \left(\frac{7}{2} + \frac{5}{2}x^4\right)$
Simplify: $\frac{12}{6} = 2$, so $2x^3$
Now group:
- $\frac{5}{2}x^4$
- $2x^3$
- $\frac{2}{3} + \frac{7}{2} = \frac{4}{6} + \frac{21}{6} = \frac{25}{6}$
So:
$$
= \frac{5}{2}x^4 + 2x^3 + \frac{25}{6}
$$
✔ Answer: $\frac{5}{2}x^4 + 2x^3 + \frac{25}{6}$
---
#### 20) $\left(\frac{19}{5}x^3 + 2x^2\right) - \left(\frac{2}{3}x^3 - \frac{25}{8}x\right)$
Distribute the minus sign:
$$
= \frac{19}{5}x^3 + 2x^2 - \frac{2}{3}x^3 + \frac{25}{8}x
$$
Combine like terms:
- $x^3$: $\frac{19}{5} - \frac{2}{3} = \frac{57 - 10}{15} = \frac{47}{15}$
- $x^2$: $2x^2$
- $x$: $\frac{25}{8}x$
So:
$$
= \frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x
$$
✔ Answer: $\frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x$
---
#### 21) $\left(-\frac{5}{3}x + \frac{5}{4}x^2\right) + \left(\frac{1}{4}x^2 - 2x^3\right)$
Group:
- $x^3$: $-2x^3$
- $x^2$: $\frac{5}{4}x^2 + \frac{1}{4}x^2 = \frac{6}{4}x^2 = \frac{3}{2}x^2$
- $x$: $-\frac{5}{3}x$
So:
$$
= -2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x
$$
✔ Answer: $-2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x$
---
#### 22) $\left(-\frac{10}{7}x^3 - \frac{4}{3}\right) + \left(\frac{29}{6} + \frac{1}{5}x^3\right)$
Group:
- $x^3$: $-\frac{10}{7}x^3 + \frac{1}{5}x^3$
LCM of 7 and 5 is 35:
$$
= -\frac{50}{35}x^3 + \frac{7}{35}x^3 = -\frac{43}{35}x^3
$$
Constants: $-\frac{4}{3} + \frac{29}{6}$
LCM = 6:
$$
= -\frac{8}{6} + \frac{29}{6} = \frac{21}{6} = \frac{7}{2}
$$
So:
$$
= -\frac{43}{35}x^3 + \frac{7}{2}
$$
✔ Answer: $-\frac{43}{35}x^3 + \frac{7}{2}$
---
| Problem | Answer |
|--------|--------|
| 1 | $-\frac{17}{30}$ |
| 2 | $\frac{1}{6}$ |
| 3 | $-\frac{19}{12}$ |
| 4 | $\frac{1}{8}$ |
| 5 | $\frac{7}{24}$ |
| 6 | $-\frac{11}{8}$ |
| 7 | $-\frac{38}{35}$ |
| 8 | $\frac{3}{2}$ |
| 9 | $-\frac{7}{2}$ |
| 10 | $\frac{9}{4}$ |
| 11 | $\frac{5}{2}$ |
| 12 | $-\frac{29}{12}$ |
| 13 | $\frac{89}{84}$ |
| 14 | $\frac{11}{6}$ |
| 15 | $\frac{37}{15}$ |
| 16 | $\frac{62}{21}$ |
| 17 | $-\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}$ |
| 18 | $\frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}$ |
| 19 | $\frac{5}{2}x^4 + 2x^3 + \frac{25}{6}$ |
| 20 | $\frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x$ |
| 21 | $-2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x$ |
| 22 | $-\frac{43}{35}x^3 + \frac{7}{2}$ |
Let me know if you'd like these answers boxed or formatted differently!
---
Part 1: Evaluate Each Expression
We will evaluate each expression using fraction arithmetic rules (common denominators, signs, etc.).
---
#### 1) $\left(-\frac{1}{6}\right) - \frac{2}{5}$
Find a common denominator: $30$
$$
= \left(-\frac{5}{30}\right) - \frac{12}{30} = -\frac{17}{30}
$$
✔ Answer: $-\frac{17}{30}$
---
#### 2) $(-2\frac{1}{2}) + 2\frac{2}{3}$
Convert to improper fractions:
- $-2\frac{1}{2} = -\frac{5}{2}$
- $2\frac{2}{3} = \frac{8}{3}$
Common denominator: 6
$$
= -\frac{15}{6} + \frac{16}{6} = \frac{1}{6}
$$
✔ Answer: $\frac{1}{6}$
---
#### 3) $\left(-\frac{1}{4}\right) - 1\frac{1}{3}$
Convert mixed number: $1\frac{1}{3} = \frac{4}{3}$
So:
$$
= -\frac{1}{4} - \frac{4}{3}
$$
Common denominator: 12
$$
= -\frac{3}{12} - \frac{16}{12} = -\frac{19}{12}
$$
Or as mixed number: $-1\frac{7}{12}$
✔ Answer: $-\frac{19}{12}$ or $-1\frac{7}{12}$
---
#### 4) $\left(-\frac{1}{4}\right) - \left(-\frac{3}{8}\right)$
Subtracting a negative is adding:
$$
= -\frac{1}{4} + \frac{3}{8}
$$
Common denominator: 8
$$
= -\frac{2}{8} + \frac{3}{8} = \frac{1}{8}
$$
✔ Answer: $\frac{1}{8}$
---
#### 5) $\frac{13}{8} - 1\frac{1}{3}$
Convert $1\frac{1}{3} = \frac{4}{3}$
Now:
$$
= \frac{13}{8} - \frac{4}{3}
$$
LCM of 8 and 3 is 24:
$$
= \frac{39}{24} - \frac{32}{24} = \frac{7}{24}
$$
✔ Answer: $\frac{7}{24}$
---
#### 6) $\left(-\frac{1}{2}\right) + \left(-\frac{7}{8}\right)$
Same sign → add absolute values, keep negative:
$$
= -\left(\frac{1}{2} + \frac{7}{8}\right) = -\left(\frac{4}{8} + \frac{7}{8}\right) = -\frac{11}{8}
$$
Or: $-1\frac{3}{8}$
✔ Answer: $-\frac{11}{8}$
---
#### 7) $\frac{5}{7} + \left(-\frac{9}{5}\right)$
$$
= \frac{5}{7} - \frac{9}{5}
$$
LCM of 7 and 5 is 35:
$$
= \frac{25}{35} - \frac{63}{35} = -\frac{38}{35}
$$
Or: $-1\frac{3}{35}$
✔ Answer: $-\frac{38}{35}$
---
#### 8) $(-2) + 3\frac{1}{2}$
Convert: $3\frac{1}{2} = \frac{7}{2}$
$$
= -2 + \frac{7}{2} = -\frac{4}{2} + \frac{7}{2} = \frac{3}{2}
$$
Or: $1\frac{1}{2}$
✔ Answer: $\frac{3}{2}$
---
#### 9) $(-2) - \frac{3}{2}$
$$
= -2 - \frac{3}{2} = -\frac{4}{2} - \frac{3}{2} = -\frac{7}{2}
$$
Or: $-3\frac{1}{2}$
✔ Answer: $-\frac{7}{2}$
---
#### 10) $(-1) - \left(-3\frac{1}{4}\right)$
Subtracting a negative → add:
$$
= -1 + 3\frac{1}{4} = -1 + \frac{13}{4} = -\frac{4}{4} + \frac{13}{4} = \frac{9}{4}
$$
Or: $2\frac{1}{4}$
✔ Answer: $\frac{9}{4}$
---
#### 11) $\left(-\frac{2}{8}\right) + 3\frac{1}{2} - \frac{3}{4}$
Simplify $-\frac{2}{8} = -\frac{1}{4}$
$3\frac{1}{2} = \frac{7}{2}$
Now:
$$
= -\frac{1}{4} + \frac{7}{2} - \frac{3}{4}
$$
Convert all to fourths:
$$
= -\frac{1}{4} + \frac{14}{4} - \frac{3}{4} = \frac{10}{4} = \frac{5}{2}
$$
Or: $2\frac{1}{2}$
✔ Answer: $\frac{5}{2}$
---
#### 12) $\frac{3}{4} - \frac{7}{6} - 2$
Convert to common denominator (LCM of 4, 6, 1 is 12):
$$
= \frac{9}{12} - \frac{14}{12} - \frac{24}{12} = \frac{9 - 14 - 24}{12} = \frac{-29}{12}
$$
Or: $-2\frac{5}{12}$
✔ Answer: $-\frac{29}{12}$
---
#### 13) $\left(-\frac{3}{4}\right) + \frac{2}{3} + 3 - 1\frac{6}{7}$
Convert all to improper fractions where needed:
- $3 = \frac{3}{1}$
- $1\frac{6}{7} = \frac{13}{7}$
So:
$$
= -\frac{3}{4} + \frac{2}{3} + \frac{3}{1} - \frac{13}{7}
$$
Find LCM of 4, 3, 1, 7 → 84
Convert each:
- $-\frac{3}{4} = -\frac{63}{84}$
- $\frac{2}{3} = \frac{56}{84}$
- $\frac{3}{1} = \frac{252}{84}$
- $-\frac{13}{7} = -\frac{156}{84}$
Add:
$$
= -63 + 56 + 252 - 156 = (-63 + 56) = -7; (252 - 156) = 96 → -7 + 96 = 89
$$
So: $\frac{89}{84}$
Or: $1\frac{5}{84}$
✔ Answer: $\frac{89}{84}$
---
#### 14) $\left(-\frac{3}{2}\right) - 4\left(-2\right) - 4\frac{2}{3}$
First: $-4(-2) = +8$
$4\frac{2}{3} = \frac{14}{3}$
So:
$$
= -\frac{3}{2} + 8 - \frac{14}{3}
$$
Convert to common denominator (LCM of 2,1,3 is 6)
- $-\frac{3}{2} = -\frac{9}{6}$
- $8 = \frac{48}{6}$
- $-\frac{14}{3} = -\frac{28}{6}$
Now:
$$
= -\frac{9}{6} + \frac{48}{6} - \frac{28}{6} = \frac{11}{6}
$$
Or: $1\frac{5}{6}$
✔ Answer: $\frac{11}{6}$
---
#### 15) $1 + \frac{9}{5} + 3\frac{1}{6} + \left(-3\frac{1}{2}\right)$
Convert all:
- $1 = 1$
- $\frac{9}{5} = \frac{9}{5}$
- $3\frac{1}{6} = \frac{19}{6}$
- $-3\frac{1}{2} = -\frac{7}{2}$
Now:
$$
= 1 + \frac{9}{5} + \frac{19}{6} - \frac{7}{2}
$$
LCM of 1,5,6,2 → 30
Convert:
- $1 = \frac{30}{30}$
- $\frac{9}{5} = \frac{54}{30}$
- $\frac{19}{6} = \frac{95}{30}$
- $-\frac{7}{2} = -\frac{105}{30}$
Add:
$$
= \frac{30 + 54 + 95 - 105}{30} = \frac{74}{30} = \frac{37}{15}
$$
Or: $2\frac{7}{15}$
✔ Answer: $\frac{37}{15}$
---
#### 16) $\left(-\frac{2}{3}\right) - \left(-\frac{1}{3}\right) + 2 - \left(-\frac{9}{7}\right)$
Simplify negatives:
- $-\left(-\frac{1}{3}\right) = +\frac{1}{3}$
- $-\left(-\frac{9}{7}\right) = +\frac{9}{7}$
So:
$$
= -\frac{2}{3} + \frac{1}{3} + 2 + \frac{9}{7}
$$
Combine like terms:
- $-\frac{2}{3} + \frac{1}{3} = -\frac{1}{3}$
Now:
$$
= -\frac{1}{3} + 2 + \frac{9}{7}
$$
Convert to common denominator (LCM of 3,1,7 = 21)
- $-\frac{1}{3} = -\frac{7}{21}$
- $2 = \frac{42}{21}$
- $\frac{9}{7} = \frac{27}{21}$
Add:
$$
= -\frac{7}{21} + \frac{42}{21} + \frac{27}{21} = \frac{62}{21}
$$
Or: $2\frac{20}{21}$
✔ Answer: $\frac{62}{21}$
---
Part 2: Simplify Each Expression
These are algebraic expressions with variables. Combine like terms.
---
#### 17) $\left(-\frac{3}{2}x - 1\right) + \left(-\frac{5}{3}x^2 + \frac{4}{3}\right)$
Group like terms:
- $-\frac{5}{3}x^2$
- $-\frac{3}{2}x$
- $-1 + \frac{4}{3} = \frac{-3 + 4}{3} = \frac{1}{3}$
So:
$$
= -\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}
$$
✔ Answer: $-\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}$
---
#### 18) $\left(\frac{14}{3} - \frac{1}{2}\right) + \left(\frac{7}{2}x + \frac{4}{3}x^2\right)$
First: $\frac{14}{3} - \frac{1}{2}$
LCM = 6:
$$
= \frac{28}{6} - \frac{3}{6} = \frac{25}{6}
$$
Then: $\frac{7}{2}x + \frac{4}{3}x^2$
So combine:
$$
= \frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}
$$
✔ Answer: $\frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}$
---
#### 19) $\left(\frac{12}{6}x^3 + \frac{2}{3}\right) + \left(\frac{7}{2} + \frac{5}{2}x^4\right)$
Simplify: $\frac{12}{6} = 2$, so $2x^3$
Now group:
- $\frac{5}{2}x^4$
- $2x^3$
- $\frac{2}{3} + \frac{7}{2} = \frac{4}{6} + \frac{21}{6} = \frac{25}{6}$
So:
$$
= \frac{5}{2}x^4 + 2x^3 + \frac{25}{6}
$$
✔ Answer: $\frac{5}{2}x^4 + 2x^3 + \frac{25}{6}$
---
#### 20) $\left(\frac{19}{5}x^3 + 2x^2\right) - \left(\frac{2}{3}x^3 - \frac{25}{8}x\right)$
Distribute the minus sign:
$$
= \frac{19}{5}x^3 + 2x^2 - \frac{2}{3}x^3 + \frac{25}{8}x
$$
Combine like terms:
- $x^3$: $\frac{19}{5} - \frac{2}{3} = \frac{57 - 10}{15} = \frac{47}{15}$
- $x^2$: $2x^2$
- $x$: $\frac{25}{8}x$
So:
$$
= \frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x
$$
✔ Answer: $\frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x$
---
#### 21) $\left(-\frac{5}{3}x + \frac{5}{4}x^2\right) + \left(\frac{1}{4}x^2 - 2x^3\right)$
Group:
- $x^3$: $-2x^3$
- $x^2$: $\frac{5}{4}x^2 + \frac{1}{4}x^2 = \frac{6}{4}x^2 = \frac{3}{2}x^2$
- $x$: $-\frac{5}{3}x$
So:
$$
= -2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x
$$
✔ Answer: $-2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x$
---
#### 22) $\left(-\frac{10}{7}x^3 - \frac{4}{3}\right) + \left(\frac{29}{6} + \frac{1}{5}x^3\right)$
Group:
- $x^3$: $-\frac{10}{7}x^3 + \frac{1}{5}x^3$
LCM of 7 and 5 is 35:
$$
= -\frac{50}{35}x^3 + \frac{7}{35}x^3 = -\frac{43}{35}x^3
$$
Constants: $-\frac{4}{3} + \frac{29}{6}$
LCM = 6:
$$
= -\frac{8}{6} + \frac{29}{6} = \frac{21}{6} = \frac{7}{2}
$$
So:
$$
= -\frac{43}{35}x^3 + \frac{7}{2}
$$
✔ Answer: $-\frac{43}{35}x^3 + \frac{7}{2}$
---
✔ Final Answers Summary
| Problem | Answer |
|--------|--------|
| 1 | $-\frac{17}{30}$ |
| 2 | $\frac{1}{6}$ |
| 3 | $-\frac{19}{12}$ |
| 4 | $\frac{1}{8}$ |
| 5 | $\frac{7}{24}$ |
| 6 | $-\frac{11}{8}$ |
| 7 | $-\frac{38}{35}$ |
| 8 | $\frac{3}{2}$ |
| 9 | $-\frac{7}{2}$ |
| 10 | $\frac{9}{4}$ |
| 11 | $\frac{5}{2}$ |
| 12 | $-\frac{29}{12}$ |
| 13 | $\frac{89}{84}$ |
| 14 | $\frac{11}{6}$ |
| 15 | $\frac{37}{15}$ |
| 16 | $\frac{62}{21}$ |
| 17 | $-\frac{5}{3}x^2 - \frac{3}{2}x + \frac{1}{3}$ |
| 18 | $\frac{4}{3}x^2 + \frac{7}{2}x + \frac{25}{6}$ |
| 19 | $\frac{5}{2}x^4 + 2x^3 + \frac{25}{6}$ |
| 20 | $\frac{47}{15}x^3 + 2x^2 + \frac{25}{8}x$ |
| 21 | $-2x^3 + \frac{3}{2}x^2 - \frac{5}{3}x$ |
| 22 | $-\frac{43}{35}x^3 + \frac{7}{2}$ |
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Parent Tip: Review the logic above to help your child master the concept of precalculus worksheet free printable.