Question

what is the decimal .387123 rounded to the nearest thousand

Answer 1

It is the nearest thousandth which is the third decimal place. The answer would be .387 unless the 1 was a 5 or higher then it would be .388

Answer 2

0.387123

Note the place value of each digit

0
.
3 (tenths)
8 (hundredths)
7 (thousandths)
1 (ten thousandths)
2 (hundred thousandths)
3 (millionths)

to find the nearest thousandths, look at the place value of the ten thousandths. It is a 1. Because it is less than 5, you round down.

0.387123 becomes 0.387

0.387 is your answer

hope this helps