Table 1 shows the rate of transpiration in four different plant species.
| Plant species | Rate of transpiration (arbitrary units) |
|---|---|
| W | 385 |
| X | 165 |
| Y | 245 |
| Z | 78 |
Calculate how many times greater the rate of transpiration of species W is than the rate of transpiration of species Y.
Give your answer to 2 significant figures.