1. **Problem 11:** What percent of this circle is shaded? Since the problem does not provide a specific fraction or angle of the shaded part, we cannot calculate the exact percentage. Usually, the percent shaded is calculated by $\frac{\text{shaded area}}{\text{total area}} \times 100\%$. 2. **Problem 12a:** Volume of a cube with edge length 3 cm. Formula: $V = s^3$, where $s$ is the edge length. Calculation: $$V = 3^3 = 27\text{ cm}^3$$ 3. **Problem 12b:** Surface area of the cube. Formula: $SA = 6s^2$ Calculation: $$SA = 6 \times 3^2 = 6 \times 9 = 54\text{ cm}^2$$ 4. **Problem 13:** Collect like terms in $2x + 3y - 5 + x - y - 1$. Group like terms: $$2x + x = 3x$$ $$3y - y = 2y$$ $$-5 - 1 = -6$$ Final expression: $$3x + 2y - 6$$ 5. **Problem 14:** Collect like terms in $4x^2 + 2x - x - 2$. Group like terms: $$2x - x = x$$ Final expression: $$4x^2 + x - 2$$ 6. **Problem 15:** Complete the table. a. Fraction corresponding to decimal 0.125: $$0.125 = \frac{1}{8}$$ b. Percent corresponding to 0.125: $$0.125 \times 100 = 12.5\%$$ c. Decimal corresponding to $\frac{3}{8}$: $$\frac{3}{8} = 0.375$$ d. Percent corresponding to $\frac{3}{8}$: $$0.375 \times 100 = 37.5\%$$ 7. **Problem 16:** Simplify $\frac{60}{60}$. Since numerator and denominator are equal: $$\frac{\cancel{60}}{\cancel{60}} = 1$$ 8. **Problem 17:** Sale price is what percent of regular price? Given regular price = 24, sale price = 18. Formula: $$\text{Percent} = \frac{\text{sale price}}{\text{regular price}} \times 100\%$$ Calculation: $$\frac{18}{24} \times 100 = 0.75 \times 100 = 75\%$$ 9. **Problem 18:** Auditorium seated 375, which is 30% of those who wanted seats. How many wanted seats but could not get one? Let total wanting seats be $x$. Equation: $$0.30x = 375$$ Solve for $x$: $$x = \frac{375}{0.30} = 1250$$ Number who could not get seats: $$1250 - 375 = 875$$ 10. **Problem 19:** Twenty-four is 25% of what number? Let the number be $x$. Equation: $$24 = 0.25x$$ Solve for $x$: $$x = \frac{24}{0.25} = 96$$ 11. **Problem 20a:** Classify the quadrilateral (right trapezoid with bases 30 mm and 10 mm, height 50 mm). It is a trapezoid because it has one pair of parallel sides (bases). 12. **Problem 20b:** Find perimeter. Perimeter = sum of all sides. Given bases: 30 mm and 10 mm, legs: 50 mm and 50 mm. $$P = 30 + 10 + 50 + 50 = 140\text{ mm}$$ 13. **Problem 20c:** Find area. Formula for trapezoid area: $$A = \frac{(b_1 + b_2)}{2} \times h$$ Calculation: $$A = \frac{30 + 10}{2} \times 50 = 20 \times 50 = 1000\text{ mm}^2$$ 14. **Problem 21:** Use $y = x - 5$ to find missing $y$ values for $x = 3, 7, 5$. Calculate: $$y(3) = 3 - 5 = -2$$ $$y(7) = 7 - 5 = 2$$ $$y(5) = 5 - 5 = 0$$ The line crosses the y-axis at $x=0$, so: $$y = 0 - 5 = -5$$ 15. **Problem 22a:** Multiply $9 \times 10^4 \times 7 \times 10^9$. Group coefficients and powers: $$9 \times 7 = 63$$ $$10^4 \times 10^9 = 10^{4+9} = 10^{13}$$ Product: $$63 \times 10^{13} = 6.3 \times 10^{14}$$ 16. **Problem 22b:** Multiply $(9 \times 10^4)(4 \times 10^7)$. Coefficients: $$9 \times 4 = 36$$ Powers: $$10^4 \times 10^7 = 10^{11}$$ Product: $$36 \times 10^{11} = 3.6 \times 10^{12}$$ 17. **Problem 23:** Solve $8x - 5 = 2$. Add 5 to both sides: $$8x - 5 + 5 = 2 + 5$$ $$8x = 7$$ Divide both sides by 8: $$x = \frac{7}{8}$$ 18. **Problem 24:** Solve $\frac{6}{m} = 90$. Multiply both sides by $m$: $$6 = 90m$$ Divide both sides by 90: $$m = \frac{6}{90} = \frac{1}{15}$$ 19. **Problem 25a:** Find coordinates of $M$ for rectangle $JKLM$ with vertices $J(-4,2), K(0,2), L(0,0)$. Since $JKLM$ is a rectangle, $M$ is at $(-4,0)$. 20. **Problem 25b:** Translate $JKLM$ 4 units right and 2 units down. New vertices: $J' = (-4+4, 2-2) = (0,0)$ $K' = (0+4, 2-2) = (4,0)$ $L' = (0+4, 0-2) = (4,-2)$ $M' = (-4+4, 0-2) = (0,-2)$ 21. **Problem 26:** Which does not equal $4^3 = 64$? a. $2^6 = 64$ (equals) b. $4 \times 4^2 = 4 \times 16 = 64$ (equals) c. $4^4 = 256$ (does not equal) d. $4^2 \div 4 = 16 \div 4 = 4$ (does not equal) So options c and d do not equal $4^3$. 22. **Problem 27a:** Find 50% of $3^2$. Calculate: $$3^2 = 9$$ $$50\% \times 9 = 0.5 \times 9 = 4.5$$ 23. **Problem 27b:** Is 50% of $3^2$ the same as 50% of $2^3$ or 0.12? Calculate 50% of $2^3$: $$2^3 = 8$$ $$0.5 \times 8 = 4$$ 50% of 0.12: $$0.5 \times 0.12 = 0.06$$ No, 50% of $3^2$ is 4.5, which is not equal to 4 or 0.06. 24. **Problem 28:** Simplify $6(15 - 4) - 3(-3) = 6 - 3$. Calculate left side: $$6(11) + 9 = 66 + 9 = 75$$ Right side: $$6 - 3 = 3$$ So the equation is not true as written. 25. **Problem 29a:** Simplify $(-3) - 4(-3) + (-4) + (-3) - (-4)$. Calculate stepwise: $$-3 + 12 - 4 - 3 + 4$$ Group: $$(-3 - 4 - 3) + (12 + 4) = (-10) + 16 = 6$$ 26. **Problem 29b:** Simplify $(-3) - (-5) + (-2)(+3) - (-4)$. Calculate stepwise: $$-3 + 5 - 6 + 4$$ Group: $$( -3 + 5 + 4 ) - 6 = 6 - 6 = 0$$ 27. **Problem 30a:** Simplify $(2x)(-3x)$. Multiply coefficients and variables: $$2 \times -3 = -6$$ $$x \times x = x^2$$ Result: $$-6x^2$$ 28. **Problem 30b:** Simplify $(ab)(2a - 3a)$. Simplify inside parentheses: $$2a - 3a = -a$$ Multiply: $$ab \times (-a) = -a^2 b$$ 29. **Problem 30c:** Simplify $(-3x)^2$. Square both coefficient and variable: $$(-3)^2 = 9$$ $$x^2 = x^2$$ Result: $$9x^2$$