A student estimates the number of dandelion plants growing on a lawn.
Figure 1 shows a plan of the garden.

The student places a quadrat at 10 different random positions on the lawn. The quadrat measures 50 cm×50 cm50\text{ cm} \times 50\text{ cm}50 cm×50 cm.
The mean number of dandelion plants in each quadrat is 4.5.
Calculate the total estimated number of dandelion plants on the lawn. Give your answer to 3 significant figures.