1. The problem states that on a plan drawn to a scale of 1:100, the length of a living room is 10 cm. We are asked to find the actual length in meters. 2. The scale 1:100 means that 1 cm on the plan represents 100 cm in real life. 3. Therefore, to find the actual length, multiply the length on the plan by 100: $$10\ \text{cm} \times 100 = 1000\ \text{cm}$$ 4. Since 100 cm = 1 meter, convert 1000 cm to meters: $$\frac{1000}{100} = 10\ \text{meters}$$ 5. Hence, the actual length of the living room is 10 meters. 6. Checking the given options: - A. 9.90 - C. 18.88 - D. 11.10 None of these matches 10 meters exactly, but the closest is option A, 9.90. The correct answer based on calculation is 10 m, which is not listed here. This may be a typo or approximation issue, but mathematically the answer is 10 m.