economics query

i want to know whether the answer for the price elasticty of demand question is correct or not. please tell me how

suppose a deptmnt stoe has a sale on its silverware. if the price of  a plate setting is reduced from rs 300 to rs 200 and the quantity demamded increases from 3000 plate settings to 5000 plate settings, what isprice elasticity of demand

a)0.8

b)1.0

c)1.25

d)1.50

correct answer is c