Question: 1. (a) A fair die and a fair coin are thrown together once.
(i) Write down the set of all possible outcomes.
(ii) Find the probability of obtaining a prime number and a tail.
(b) The map of a field is drawn to a scale of 1 : 100. If the width and area of the field on the map are 8 cm and 88 cm2 respectively, find in m2, the area of the actual field.
(c) Copy and complete the 3 x 3 magic square such that the sum of the numbers in each row, column and diagonal is equal to 21.
10 3
7
2.
1. **Problem Statement:**
(a)(i) List all possible outcomes when a fair die and a fair coin are thrown together once.
(a)(ii) Find the probability of obtaining a prime number on the die and a tail on the coin.
(b) Given a map scale of 1:100, width 8 cm and area 88 cm² on the map, find the actual area in m².
(c) Complete the 3x3 magic square so each row, column, and diagonal sums to 21, given some numbers.
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2. **Step 1: (a)(i) Set of all possible outcomes**
- The die has outcomes: $\{1,2,3,4,5,6\}$.
- The coin has outcomes: $\{H, T\}$.
- The combined outcomes are pairs $(\text{die}, \text{coin})$.
- So the sample space is:
$$\{(1,H),(1,T),(2,H),(2,T),(3,H),(3,T),(4,H),(4,T),(5,H),(5,T),(6,H),(6,T)\}$$
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3. **Step 2: (a)(ii) Probability of prime number and tail**
- Prime numbers on a die: $2,3,5$.
- Outcomes with prime and tail:
$$\{(2,T),(3,T),(5,T)\}$$
- Number of favorable outcomes = 3.
- Total outcomes = 12.
- Probability = $\frac{3}{12} = \frac{1}{4}$.
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4. **Step 3: (b) Actual area of the field**
- Scale: $1:100$ means $1$ cm on map = $100$ cm actual.
- Width on map = $8$ cm, so actual width = $8 \times 100 = 800$ cm = $8$ m.
- Area on map = $88$ cm².
- Area scale factor = $(100)^2 = 10,000$ (since area scales by square of length scale).
- Actual area = $88 \times 10,000 = 880,000$ cm².
- Convert to m²: $880,000 \text{ cm}^2 = \frac{880,000}{10,000} = 88$ m².
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5. **Step 4: (c) Complete the magic square**
- Given partial magic square:
$$\begin{matrix}10 & 3 & x \\ y & 7 & z \\ 2 & a & b \end{matrix}$$
- Each row, column, diagonal sums to 21.
- Row 1: $10 + 3 + x = 21 \Rightarrow x = 8$.
- Row 2: $y + 7 + z = 21 \Rightarrow y + z = 14$.
- Row 3: $2 + a + b = 21 \Rightarrow a + b = 19$.
- Column 1: $10 + y + 2 = 21 \Rightarrow y = 9$.
- Column 2: $3 + 7 + a = 21 \Rightarrow a = 11$.
- Column 3: $x + z + b = 21 \Rightarrow 8 + z + b = 21 \Rightarrow z + b = 13$.
- From $y + z = 14$ and $y=9$, $z=5$.
- From $z + b = 13$ and $z=5$, $b=8$.
**Completed magic square:**
$$\begin{matrix}10 & 3 & 8 \\ 9 & 7 & 5 \\ 2 & 11 & 8 \end{matrix}$$
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**Final answers:**
- (a)(i) Sample space: $\{(1,H),(1,T),(2,H),(2,T),(3,H),(3,T),(4,H),(4,T),(5,H),(5,T),(6,H),(6,T)\}$.
- (a)(ii) Probability = $\frac{1}{4}$.
- (b) Actual area = $88$ m².
- (c) Completed magic square:
$$\begin{matrix}10 & 3 & 8 \\ 9 & 7 & 5 \\ 2 & 11 & 8 \end{matrix}$$