Translation of "Estimate" in Chinese

Try to estimate how much you spent on books.

算一算你花了多少錢買書。

How much time do you estimate it'll take you to do that?

你估计做那件事需要花费你多少时间呢？

According to an estimate, steel production will reach 100 million tons this year.

一項估計顯示，今年的鋼鉄產量將會達到一億噸。

At a rough estimate, I would say the job will take two weeks.

我想這工作粗略估計得花上兩個星期的時間。