Sugar Simplify
1. **Problem 2.1: Sugar for Treats**
Lebo has a five-cup bag of sugar and needs to use it for three recipes:
- 1 \(\frac{3}{4}\) cups for brownies
- 2 \(\frac{1}{2}\) cups for cupcakes
- \(\frac{3}{8}\) cups for cookies
2. **Convert the mixed numbers to improper fractions or decimals:**
- 1 \(\frac{3}{4}\) = \(1 + \frac{3}{4} = \frac{4}{4} + \frac{3}{4} = \frac{7}{4}\) cups
- 2 \(\frac{1}{2}\) = \(2 + \frac{1}{2} = \frac{4}{2} + \frac{1}{2} = \frac{5}{2}\) cups
- \(\frac{3}{8}\) cups stays as it is.
3. **Find a common denominator to sum the fractions:**
Denominators are 4, 2, and 8. The least common denominator is 8.
- \(\frac{7}{4} = \frac{7 \times 2}{4 \times 2} = \frac{14}{8}\)
- \(\frac{5}{2} = \frac{5 \times 4}{2 \times 4} = \frac{20}{8}\)
- \(\frac{3}{8}\) stays \(\frac{3}{8}\)
4. **Sum the sugar amounts:**
$$\frac{14}{8} + \frac{20}{8} + \frac{3}{8} = \frac{14 + 20 + 3}{8} = \frac{37}{8}$$
5. **Convert \(\frac{37}{8}\) to a mixed number:**
$$37 \div 8 = 4 \text{ remainder } 5 \implies 4 \frac{5}{8} \text{ cups}$$
6. **Compare required sugar to amount available:**
- Available sugar = 5 cups = \(5 \frac{0}{8} = \frac{40}{8}\)
- Required sugar = \(\frac{37}{8}\)
Since \(\frac{40}{8} > \frac{37}{8}\), Lebo has enough sugar.
7. **Calculate leftover sugar:**
$$\frac{40}{8} - \frac{37}{8} = \frac{3}{8}$$
Lebo will have \(\frac{3}{8}\) cups of sugar left over.
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8. **Problem 2.2: Simplify the expression**
$$-3^{2} + 4 \times (2 + 5) - (-6)$$
9. **Apply the order of operations (PEMDAS):**
- First, evaluate exponent:
$$3^{2} = 9$$
- Note the negative sign: \(-3^{2} = -(3^{2}) = -9\)
10. **Evaluate inside the parentheses:**
$$2 + 5 = 7$$
11. **Multiply:**
$$4 \times 7 = 28$$
12. **Simplify the double negative:**
$$- (-6) = +6$$
13. **Now substitute back and add: **
$$-9 + 28 + 6$$
14. **Sum:**
$$(-9 + 28) + 6 = 19 + 6 = 25$$
**Final Answers:**
- Q2.1: Lebo has enough sugar and will have \(\frac{3}{8}\) cups left.
- Q2.2: The simplified value is 25.