1. **Problem:** Calculate $27 + 0.6 + 0.02$. 2. **Formula:** Addition of decimals and whole numbers. 3. **Work:** $$27 + 0.6 + 0.02 = 27 + 0.62 = 27.62$$ 4. **Answer:** $27.62$. 1. **Problem:** Calculate $360 \div 4$. 2. **Formula:** Division. 3. **Work:** $$360 \div 4 = 90$$ 4. **Answer:** $90$. 1. **Problem:** How many edges does a cube have? 2. **Rule:** A cube has 12 edges. 3. **Answer:** $12$ edges. 1. **Problem:** I have 1 litre (1000 ml) of cola. I drink 650 ml. How much is left? 2. **Formula:** Subtraction. 3. **Work:** $$1000 - 650 = 350$$ 4. **Answer:** $350$ ml left. 1. **Problem:** Which two numbers have a sum of 15 and a product of 36? 2. **Formula:** Let the numbers be $x$ and $y$. $$x + y = 15$$ $$xy = 36$$ 3. **Work:** From $x + y = 15$, $y = 15 - x$. Substitute into product: $$x(15 - x) = 36$$ $$15x - x^2 = 36$$ $$x^2 - 15x + 36 = 0$$ 4. **Solve quadratic:** $$x = \frac{15 \pm \sqrt{15^2 - 4 \times 36}}{2} = \frac{15 \pm \sqrt{225 - 144}}{2} = \frac{15 \pm \sqrt{81}}{2} = \frac{15 \pm 9}{2}$$ 5. **Solutions:** $$x = \frac{15 + 9}{2} = 12, \quad y = 3$$ $$x = \frac{15 - 9}{2} = 3, \quad y = 12$$ 6. **Answer:** The numbers are $3$ and $12$. 1. **Problem:** How many quarts make 5 gallons? 2. **Rule:** 1 gallon = 4 quarts. 3. **Work:** $$5 \times 4 = 20$$ 4. **Answer:** $20$ quarts. 1. **Problem:** Calculate $4 \frac{1}{3} - \frac{2}{3}$. 2. **Convert mixed number:** $$4 \frac{1}{3} = \frac{13}{3}$$ 3. **Work:** $$\frac{13}{3} - \frac{2}{3} = \frac{13 - 2}{3} = \frac{11}{3} = 3 \frac{2}{3}$$ 4. **Answer:** $3 \frac{2}{3}$. 1. **Problem:** Write down all the factors of 33. 2. **Factors:** Numbers that divide 33 exactly. 3. **Answer:** $1, 3, 11, 33$ 1. **Problem:** Which of these numbers is not a multiple of 3? 81, 111, 73, 27, 105 2. **Rule:** A multiple of 3 has sum of digits divisible by 3. 3. **Check:** - 81: $8+1=9$ divisible by 3 - 111: $1+1+1=3$ divisible by 3 - 73: $7+3=10$ not divisible by 3 - 27: $2+7=9$ divisible by 3 - 105: $1+0+5=6$ divisible by 3 4. **Answer:** $73$ is not a multiple of 3. 1. **Problem:** Flight time from Houston to Orlando is 2 hours 20 minutes. Arrival time is 4:15 pm. What time did I set off? 2. **Formula:** Departure time = Arrival time - Flight time. 3. **Work:** $$4:15 \text{ pm} - 2 \text{ hours } 20 \text{ minutes} = 1:55 \text{ pm}$$ 4. **Answer:** Departure time is $1:55$ pm. 1. **Problem:** What is $\frac{1}{5}$ of 20 m? 2. **Formula:** Multiply fraction by number. 3. **Work:** $$\frac{1}{5} \times 20 = 4$$ 4. **Answer:** $4$ m. 1. **Problem:** What is the value of $3 \times (2 + 5)$? 2. **Formula:** Use order of operations. 3. **Work:** $$3 \times (2 + 5) = 3 \times 7 = 21$$ 4. **Answer:** $21$. 1. **Problem:** Adult entry $12$, child entry $8$. Pay for 2 adults and 3 children with 50. How much change? 2. **Formula:** Total cost = $2 \times 12 + 3 \times 8$ 3. **Work:** $$2 \times 12 = 24$$ $$3 \times 8 = 24$$ $$24 + 24 = 48$$ 4. **Change:** $$50 - 48 = 2$$ 5. **Answer:** Change is $2$. 1. **Problem:** The time is a quarter to 7 in the evening. Write this in 24-hour clock. 2. **Rule:** Quarter to 7 means 6:45 pm. 3. **Convert:** $$6:45 \text{ pm} = 18:45$$ 4. **Answer:** $18:45$. 1. **Problem:** A kid's skipping rope is 7 ft long. How many skipping ropes can be cut from a 10-yard rope? 2. **Convert yards to feet:** $$1 \text{ yard} = 3 \text{ feet}$$ $$10 \text{ yards} = 30 \text{ feet}$$ 3. **Work:** $$\frac{30}{7} = 4 \text{ ropes with } 2 \text{ feet left}$$ 4. **Answer:** $4$ ropes. 1. **Problem:** Convert 55 ft to yards and feet. 2. **Formula:** $$1 \text{ yard} = 3 \text{ feet}$$ 3. **Work:** $$55 \div 3 = 18 \text{ yards } \text{ remainder } 1 \text{ foot}$$ 4. **Answer:** $18$ yd $1$ ft. 1. **Problem:** Write down all prime numbers between 10 and 20. 2. **Prime numbers:** Numbers divisible only by 1 and themselves. 3. **Answer:** $11, 13, 17, 19$ 1. **Problem:** How many thirds make 5? 2. **Formula:** $$\frac{1}{3} \times n = 5$$ 3. **Work:** $$n = 5 \times 3 = 15$$ 4. **Answer:** $15$ thirds.