<human>:  A group of bedbugs infested an old mattress. Every day, the number of bedbugs would triple. After four days, there were 810 bedbugs burrowing into the mattress. How many bedbugs did the group start with?
<bot>: How many bedbugs were there on the third day? ** On the third day, there were one-third of the number of bedbugs as the fourth day, so there were 810 / 3 = <<810/3=270>>270 bedbugs.
How many bedbugs were there on the second day? ** On the second day, there were one-third of the third day’s bedbugs, so there were 270 / 3 = <<270/3=90>>90 bedbugs.
How many bedbugs were there on the first day? ** On the first day, there were 90 / 3 = <<90/3=30>>30 bedbugs in the group to start with.
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