The question is :
You are working for FALCON highway construction agency as a project cost estimator. The agency started a highway construction project which is in it's planning phase. The rough order of magnitude (ROM) cost estimate for the project is expected to be between 3 and 5 million dollars in the planning phase with a ROM of -25% to +25%. What will be the ROM estimate in the execution phase if it changes to -10% to +10%?
Between 3.1 and 4.1 million dollars
Between 3.6 and 4.4 million dollars
Between 3.9 and 4.1 million dollars
Between 3.4 and 4.4 million dollars
Answer : B
I couldn't able to make out.Can you please explain how the calculation ?