profit and loss

The cost price of an item increases by 10% first, then by 10% next and by 10% yet again finally. If the last10% increase is equivalent to an increase of $ 121, what was the first 10% equivalent to?

Answer:

Last but one cost price = 121/ 0.1 = 1210.

Cost price after first increase = 1210 /1.1 = 1100

Cost price initially = 1100/1.1 = 1000

So, first 10% is equivalent to = 1100 – 1000 = $ 100.

 

check:
final cost price = 1000x1.1x1.1x1.1 = 1331
last but one cost price = 1000 x 1.1 x 1.1 = 1210
difference = 1331 - 1210 = 121