A class 2 estimate of the ISBL capital cost of building a 200,000 MMlb/yr ethylene cracking plant has been stated as $850 MM -5%/+10%. The plant is to be built as an expansion of an existing site and offsite costs are estimated to be between $170 MM and $250 MM. Estimate a value for the total project cost that will give 98% confidence that the project can be carried out within the amount estimated.