Review of Addition, Subtraction, Multiplication and Division ... - Free Printable

The image appears to be a math worksheet with various problems involving arithmetic operations, fractions, and basic algebra. Below, I will solve each problem step by step.

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Problem 1:

$$
67 - 21 = \boxed{46}
$$

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Problem 2:

$$
2.637 + 8.323 = \boxed{10.960}
$$

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Problem 3:

$$
48 \div 19 = \boxed{\frac{48}{19}}
$$
(Note: This is already in its simplest fractional form.)

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Problem 4:

$$
928 - 85 = \boxed{843}
$$

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Problem 5:

$$
21.306 - 3.714 = \boxed{17.592}
$$

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Problem 6:

$$
x - 9 = 7 \implies x = 7 + 9 = \boxed{16}
$$

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Problem 7:

$$
x - 18 = 14 \implies x = 14 + 18 = \boxed{32}
$$

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Problem 8:

$$
627 \div 5 = \boxed{125.4}
$$

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Problem 9:

$$
9 \times 7 = \boxed{63}
$$

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Problem 10:

$$
87 \div 7 = \boxed{12.428571\ldots} \quad \text{(or approximately } 12.43\text{)}
$$

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Problem 11:

$$
627 \div 33 = \boxed{19}
$$

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Problem 12:

$$
263 \div 724 = \boxed{\frac{263}{724}}
$$
(Note: This is already in its simplest fractional form.)

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Problem 13:

$$
\sqrt{81} = \boxed{9}
$$

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Problem 14:

$$
\sqrt{53} = \boxed{\sqrt{53}}
$$
(Note: This is an irrational number and cannot be simplified further without approximation.)

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Problem 15:

$$
\sqrt{156} = \boxed{\sqrt{156}}
$$
(Note: This is an irrational number and cannot be simplified further without approximation.)

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Problem 16:

$$
\frac{35}{702} = \boxed{\frac{35}{702}}
$$
(Note: This fraction is already in its simplest form.)

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Problem 17:

$$
\frac{43}{824} = \boxed{\frac{43}{824}}
$$
(Note: This fraction is already in its simplest form.)

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Problem 18:

$$
\frac{14}{21} = \boxed{\frac{2}{3}}
$$
(Simplify by dividing numerator and denominator by their greatest common divisor, which is 7.)

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Problem 19:

$$
\frac{20}{33} = \boxed{\frac{20}{33}}
$$
(Note: This fraction is already in its simplest form.)

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Problem 20:

$$
\frac{12}{7} = \boxed{\frac{12}{7}}
$$
(Note: This fraction is already in its simplest form.)

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Problem 21:

$$
\frac{26}{4} = \boxed{\frac{13}{2}} \quad \text{(or } 6.5\text{)}
$$
(Simplify by dividing numerator and denominator by their greatest common divisor, which is 2.)

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Problem 22:

$$
\frac{1}{3} + \frac{1}{3} = \boxed{\frac{2}{3}}
$$
(Add the fractions directly since they have the same denominator.)

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Problem 23:

$$
3 \frac{2}{7} \cdot 1 \frac{1}{3} = \left(\frac{23}{7}\right) \cdot \left(\frac{4}{3}\right) = \frac{23 \cdot 4}{7 \cdot 3} = \frac{92}{21} = \boxed{\frac{92}{21}}
$$
(Convert mixed numbers to improper fractions, multiply, and simplify if possible.)

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Problem 24:

$$
\frac{7}{9} - \frac{2}{9} = \boxed{\frac{5}{9}}
$$
(Subtract the numerators directly since the denominators are the same.)

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Problem 25:

$$
7 - \frac{3}{5} = \frac{35}{5} - \frac{3}{5} = \frac{32}{5} = \boxed{\frac{32}{5}}
$$
(Convert 7 to a fraction with denominator 5, subtract, and simplify if possible.)

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Problem 26:

$$
2 \frac{3}{7} - 1 \frac{2}{7} = \left(\frac{17}{7}\right) - \left(\frac{9}{7}\right) = \frac{17 - 9}{7} = \frac{8}{7} = \boxed{\frac{8}{7}}
$$
(Convert mixed numbers to improper fractions, subtract, and simplify if possible.)

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Problem 27:

$$
3 \frac{4}{9} - 3 \frac{3}{9} = \left(\frac{31}{9}\right) - \left(\frac{30}{9}\right) = \frac{31 - 30}{9} = \frac{1}{9} = \boxed{\frac{1}{9}}
$$
(Convert mixed numbers to improper fractions, subtract, and simplify if possible.)

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Final Answer:

$$
\boxed{
\begin{array}{l}
1. 46 \\
2. 10.960 \\
3. \frac{48}{19} \\
4. 843 \\
5. 17.592 \\
6. 16 \\
7. 32 \\
8. 125.4 \\
9. 63 \\
10. 12.428571\ldots \\
11. 19 \\
12. \frac{263}{724} \\
13. 9 \\
14. \sqrt{53} \\
15. \sqrt{156} \\
16. \frac{35}{702} \\
17. \frac{43}{824} \\
18. \frac{2}{3} \\
19. \frac{20}{33} \\
20. \frac{12}{7} \\
21. \frac{13}{2} \\
22. \frac{2}{3} \\
23. \frac{92}{21} \\
24. \frac{5}{9} \\
25. \frac{32}{5} \\
26. \frac{8}{7} \\
27. \frac{1}{9}
\end{array}
}
$$