Org Agenda schedule number of hours allocated to a task

Question

Is there a way to tell Org Agenda to schedule X number of hours for a task without a specific start-end time? Presently, the standard format is this: SCHEDULED: <2019-06-20 Thu 9:00-12:00>

Answer 1

Do you mean to be using an effort estimate instead of a scheduled time?

An effort estimate is a property, stored in the property drawer, like this:

* TODO Something that can be done in 5 minutes
  :PROPERTIES:
  :Effort:   0:05
  :END:

Effort estimates are completely separate from scheduled or deadline times, and describe how long a task might take, rather than when it should be done.

Typically, estimates are added to a task with the C-c C-x e sequence. If you have effort values that you use frequently, you can put a line like

#+PROPERTY: Effort_ALL 0 0:10 0:20 0:30 1:00 2:00 4:00 6:00 8:00

at the top of your org file, and then S-<left> and S-<right> will cycle through those values whenever you're prompted for an effort.

You may wish to check out a video tutorial on the subject:

* TODO watch org mode tutorial on effort estimates
  :PROPERTIES:
  :Effort:   0:10
  :END:
  [[https://www.youtube.com/watch?v=BeAtCVZpHCg][OrgMode E04S05: Effort estimates]]