<human>:  Bethany is working at the front desk at Joe’s Gym. There were some people lifting weights when she started her shift. Then 5 more people came in and started running on the treadmill and 2 people left. There are now 19 people in the gym. How many people were lifting weights at the start of Bethany’s shift?
<bot>: How many people came in and left after Bethany’s shift started? ** We know that 5 people came in and 2 people left after Bethany’s shift started, so there was a net change of 5 – 2 = <<5-2=3>>3 people.
How many people were lifting weights at the start of Bethany’s shift? ** If there are 19 people now in the gym and that is 3 more than when Bethany’s shift started, we know there were 19 – 3 = <<19-3=16>>16 people lifting weights at the start of her shift.
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