1. **State the problem:** We have a rectangular pastry of width 37 cm and height 20 cm with eight circles cut out. Each circle has a diameter of 8 cm. We need to find the area of the pastry left after cutting out the circles, rounded to three significant figures.
2. **Formula for area of rectangle:**
$$\text{Area}_{\text{rectangle}} = \text{width} \times \text{height}$$
3. **Formula for area of a circle:**
$$\text{Area}_{\text{circle}} = \pi r^2$$
where $r$ is the radius of the circle.
4. **Calculate the area of the rectangle:**
$$37 \times 20 = 740 \text{ cm}^2$$
5. **Calculate the radius of each circle:**
Diameter = 8 cm, so radius $r = \frac{8}{2} = 4$ cm.
6. **Calculate the area of one circle:**
$$\pi \times 4^2 = \pi \times 16 = 16\pi \text{ cm}^2$$
7. **Calculate the total area of eight circles:**
$$8 \times 16\pi = 128\pi \text{ cm}^2$$
8. **Calculate the area of pastry left:**
$$740 - 128\pi$$
9. **Evaluate the numerical value:**
Using $\pi \approx 3.1416$,
$$128 \times 3.1416 = 402.123$$
10. **Final area left:**
$$740 - 402.123 = 337.877 \text{ cm}^2$$
Rounded to three significant figures:
$$\boxed{338 \text{ cm}^2}$$
Pastry Area
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