Fence Cost
1. **State the problem:** A farmer wants to build a fence around a right-angled triangular field. One side adjacent to the right angle is 151 m, and the angle opposite this side is 52°. We need to find the total cost of the fence, given the cost is 1.42 per metre, and round the answer to the nearest pound.
2. **Identify the sides:** The triangle has a right angle, one side of length 151 m, and an angle of 52° adjacent to that side. Let's label the sides: the side of 151 m is adjacent to the 52° angle, the right angle is 90°, and the other angle is 38° (since angles in a triangle sum to 180°).
3. **Find the other two sides:**
- Let the side opposite the 52° angle be $a$.
- The side adjacent to 52° (given) is $b = 151$ m.
- The hypotenuse is $c$.
Using trigonometric ratios:
$$\sin(52^\circ) = \frac{a}{c} \Rightarrow a = c \sin(52^\circ)$$
$$\cos(52^\circ) = \frac{b}{c} \Rightarrow c = \frac{b}{\cos(52^\circ)} = \frac{151}{\cos(52^\circ)}$$
Calculate $c$:
$$c = \frac{151}{\cos(52^\circ)} \approx \frac{151}{0.6157} \approx 245.2 \text{ m}$$
Calculate $a$:
$$a = 245.2 \times \sin(52^\circ) \approx 245.2 \times 0.7880 \approx 193.1 \text{ m}$$
4. **Calculate the perimeter:**
$$P = a + b + c = 193.1 + 151 + 245.2 = 589.3 \text{ m}$$
5. **Calculate the total cost:**
$$\text{Cost} = P \times 1.42 = 589.3 \times 1.42 \approx 836.0$$
6. **Round to the nearest pound:**
$$\boxed{836}$$
The total cost of the fence is 836 to the nearest pound.