Quandaries and Queries Who is asking: Parent Level: Secondary Question: For a school science project, my son Alex is taking measurements of plant growth at regular intervals. As part of the data, he must provide the maximum percent difference observed in the categories his team has identified. So, for example he has six plants with four measurements each. (He has more, but I'll keep it simple) For the first plant he measured 2mm, 2.4mm, 2.9mm, and 3.2mm. For the 2nd, 3rd, and 4th plants, he has similar numbers. Is there a way to calculate the maximum percent difference between any two plants in his measurements during the project? Doing it for each combination would be tedious. Hi, If you have a collection of numbers and you want to find the largest percent difference between ANY pair then it is between the largest and smallest number. Certainly this isn't what you want. You want just some differences. You say you want differences between two plants. In this case I don't see a way to easily determine where you are going to find the largest percent difference. Have you looked at using a spread sheet? Penny Go to Math Central