ROM Vs Initial estimate

(1) What is the range of a rough order of magnitude (ROM) estimate? 

A. -10% to +10% 

B . -5% to +10% 

C. -50% to +50% 

D. -300 to +75

(2)  You are in the initiation phase and are doing an estimate for a project that requires a major software package for a healthcare system. What is the estimate range to use for this project?

 A. -5% to +10% 

B. -25% to +85% 

C. -10% to +25% 

D. -25% to +75%

Should we expect this sort of question on the exam? Am asking 'cos since PMBOK gave the value of ROM as hypothetical (it could be some other value), I feel the answers could vary.

ROM is +/- 50% and is used at the beginning of the project since uncertainty is the greatest at the beginning of the project.



1C and I would say 2D since it is closer to +50% compared with B +85%

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