Cost to store: $140
markup: 25%

The actual cost to the store = $140
Percentage of markup = 25%
Amount of markup in cost = (25/100) * 140 dollars
                                        = 35 dollars
Then
Sell price in the store = (35 + 140) dollars
                                   = 175 dollars
So the sell price of the product at the store after addition of the markup price will be $175.

Num of plants = (original#ofplants)*(1.6)^t