Microeconomics Questions

If price of an article decreases from Rs $P_1$ to Rs $150$, quantity demanded increases from $1000$ units to $1250$ units. If point elasticity of demand is $-1$, then find $P_1$?

Priya likes a wedding gown so much that she was willing to pay even Rs 30000 for it. Luckily she finds the same gown marked at Rs 25000 at a local store. The store is further offering a 30% discount on the gown. Priya's consumer surplus is

An increase in the price of tomatoes will cause _________.