Give the step-by-step reasoning process and then the final answer. Vanessa's new business is thriving and she frequently has orders to post. She has run out of packing peanuts for the packages and is now wondering how many orders she has sent. Each large order needs 200g of packing peanuts while small orders need just 50g of packing peanuts. If Lisa has used a total of 800g of packing peanuts and she knows she has sent 3 large orders, how many small orders has Lisa sent?
In the large orders, Lisa used 3 large orders * 200g of packing peanuts per large order = 600g of packing peanuts. The rest of the packing peanuts were used in small orders so there was a total of 800g packing peanuts - 600g of packing peanuts used in large orders = 200g of packing peanuts used in small orders. So there must have been 200g of packing peanuts / 50g of packing peanuts per small order = 4 small orders.
The final answer: 4.