申请该课程的人数为120人，而最初的估计在50到100人之间。

The number of people who applied for the course was 120 compared with an initial ___estimate of between 50 and 100.

这只是一个粗略的估计。

This is only a rough ___estimate.

承包商为项目提供了详细的估算。

The contractor provided a detailed ___estimate for the project.