To find the percentage increase in price, we need to calculate the difference between the old price and the new price, divide that by the old price, and then multiply by 100 to get the percentage increase.
The difference between the old price and the new price is:
Rs 180 - Rs 170 = Rs 10
The percentage increase in price is:
(10 / 170) x 100 = 5.88%
Therefore, the price has increased by 5.88%.