What advances did the early chinese make?

A lot they mannished to dam the yellow river , they invented paper, black powder, and theymedical knowledge was incredible that still used until now

An underestimate will occur when all the figures (or a majority of them) are rounded downward significantly. By doing this, the estimated figure will necessarily be lower than the actual calculated figure. When rounding, knowing which direction the rounding is in will give a picture of what the figure's relation to the actual answer will be.