There are 30 kg of potatoes in a wheelbarrow. A farmer adds some carrots into the wheelbarrow. The total weight of the wheelbarrow now is 110 pounds. What weight of carrots did the farmer put into the wheelbarrow? 1 kg = 2.2 pounds

First of all, you want to get all your data in the same units, so either in pounds or kg. Here, as you are told that 1kg = 2.2 pounds, it seems easier to convert the amount of potatoes from 30kg into pounds, as you only have to multiply the 30kg by 2.2 then; whereas, if you wanted to convert the total amount in the wheelbarrow from 110 pounds to kg, you would have to divide 110 by 2.2, which is harder. Multiplying 30kg by 2.2 gives you the amount of potatoes in pounds: 66 pounds. Now let x be the amount of carrots. Write a mathematical equation for the sum of the carrots and potatoes: 66 + x = 110 . This equation gives x = 110 - 66 , so x = 44 . Remember you are using pounds as unit, so therefore the weight of carrots is 44 pounds. As the question doesn't specify the units they want their answer in, you can leave it in pounds or kg.