Based on the question, we have to estimate how many cans Kayla will collect. To do this we need to get the average number of cans already collected per day. This is (25+37+42+31)/4=33.75. She has four more days to collect cans, so we would expect her to collect 4x33.75=135 more. We add this expected amount to the actual amount of 135 already collected and get an estimated total cans collected figure of 270 for the week.