The quantity demanded for a commodity rised from 100 units to 120 units when the proce declnies from $12 to $9.

The quantity demanded for a commodity rised from 100 units to 120 units when the proce declnies from $12 to $9. Again when the income rises by 5 percent, the units consumed of the commodity increase from 100 to 110. What is the income elasticity of demand for the good?