The London Independent Recently, the Independent, a daily newspaper printed in London, announced a price cut to 30 pence (P2) from 50 pence (P1). As a result, daily circulation increased from Q1 copies to Q2 copies. Using the demand elasticity and Total revenue, please state whether the price cut was a justified managerial decision or not? Total revenue= Price * quantity

So I have determined that the change in price is ( -.4), however I am not sure how I am supposed to determine what the total revenue is for each price and with the quanity being unknown. And without knowing the total revenue how am i able to judge if the price cut was jsutified?