#### Answer

I have to buy 2 kg potatoes from a grocery. I know that the price of 10 Kg potatoes is 20 dollars. How much money do I need to carry with me?

#### Work Step by Step

1. Understand the problem
Cost of 10 Kg potatoes = 20
potaoes to be bought = 2 Kg
2. Devise a Plan
Find out the unit cost of the potato, that is cost of potato per Kg, then we can multiply it with 2 to find out the cost of 2 Kg potato.
3. Carry out the plan
cost of 1 Kg Potato = 20/10 = 2 dollar
cost of 2 Kg Potato = 2 x 2 = 4 dollar
So, I need to carry 4 dollar with me.
4. Look back and check the solution
cost of 10 Kg potato = 2 x 10 = 20 dollar