Round 3,989.23655 to the nearest thousandth.
a thousandth = 1/1000 = 0.001round 4th decimal place = 55 and over rounds up, under 5 rounds downso answer is 3,989.237
a thousandth = 1/1000 = 0.001
round 4th decimal place = 5
5 and over rounds up, under 5 rounds down
so answer is 3,989.237