Question : The cost of an article worth Rs. 100 is increased by 10% first and again increased by 10%. The total increase (in Rs.) is:
Option 1: 20
Option 2: 21
Option 3: 110
Option 4: 121
Correct Answer: 21
Solution :
The cost of the article is increased by 10%.
The new cost becomes,
= 100 +
Then, this new cost is again increased by 10%.
The final cost becomes,
= 110 +
Therefore, the total increase in cost = 121 – 100 = Rs. 21
Hence, the correct answer is 21.