Loose versus packaged foodBBC Teach > Skillswise > CalculationVideo TranscriptupdownDr John Haigh: In most leading supermarkets packaged fruit and veg are often priced by the pack, while loose fruit and veg are often priced by the kilogram. For example, we found this bag of 8 pink lady apples on sale for £2.90, but you could also buy pink lady apples loose at £2.95 per kilogram.So, which is cheaper? To buy pink lady apples in a bag or to buy them loose. Let's do the maths. We have to compare like with like.This bag of 8 apples weighs 850 grams. So, how do I work out which is better value? The apples in a bag or the loose apples? I need to find the equivalent cost per kilogram for the apples in a bag. 850g is 0.85 of a kilogram and they cost £2.90. So, I divide the cost £2.90 by the weight 0.85 and get the cost per kilogram of £3.41. How much were these loose apples again? £2.95 per kilo. I don't need a pocket calculator to tell me that that's a lot less than £3.41 per kilo that the packaged apples would cost. To be exact its 46 pence per kilo to have your apples pre-packaged than to buy them loose. I know which ones I'd prefer.But, what about bananas? Buying five of them loose costs 68 pence per kilogram. Buying five of them in a packet was priced at a pound. So, I had to use the same maths to work out that the cost per kilo of buying them in a packet was £1.48. That's 80 pence more expensive per kilogram just for having them in a bag.It was the same with brown onions. £1.00 per kilo loose. £1.88 per kilo in a net. So, 88p per kilo more expensive just for being in a net. And, what about red onions? Loose 90p per kilo. In a net £1.70 per kilo. That's 80p per kilo more.Most of the time loose fruit and veg is cheaper than packaged, But, not always. Take pears for example. At three leading supermarkets, conference pears were cheaper in package than loose. Take this example, loose these pears are £2.25 per kilogram. But, in a pack they work out at £1.29 per kilogram.Just goes to show it's always worth doing the Maths.