Question

The area of the windscreen of a bus is 1.21 m². In a photograph of the bus, the windscreen appears as a rectangle 12 cm by 3 cm. Find the length and breadth of the real windscreen.​

Answer 1

The area of the rectangle in the photograph is:

length x breadth = 12 cm x 3 cm = 36 cm²

Since the photograph and the actual bus are proportional, we can express the actual length and breadth of the windscreen as follows, where k is the proportionality constant:

length_actual = k * 12 cm

breadth_actual = k * 3 cm

We can find k by setting the area of the actual windscreen equal to 1.21 m² and the area of the rectangle in the photo equal to 36 cm²:

1.21 m² = (100 cm)² * k²

k = √(1.21 m² / (100 cm)²) = 0.11

Now we can find the actual length and breadth of the windscreen:

length_actual = k * 12 cm = 0.11 * 12 cm = 1.32 m

breadth_actual = k * 3 cm = 0.11 * 3 cm = 0.33 m

Therefore, the actual length and breadth of the windscreen are 1.32 meters and 0.33 meters, respectively.