Ms. johnston's students counted by fives. the first person said, "five." the next said, "ten"; the next "15." they went all the way up to 100. how many students counted to get to 100? bobby said, "50." when asked how he knew, he said, "because 5 is half of 10, and 50 is the same number as 5, just with a 0, and 10 is the same as 100 just with another 0."

how are you going to respond to bobby? post your response by wednesday. reply you other group members by sunday - you agree with their approach to bobby? how does it compare to your answer?