Which of the following would be the impact upon a project if the CPI for the project is .75?

The cost performance index (CPI) measures the value of the work completed at the
measurement date against the actual cost. It is the most critical of all the EVM measurements according to the PMBOK Guide because it tells you the cost efficiency for the workcompleted to date or at the completion of the project. If

CPI is greater than 1, you are spending less than anticipated at the measurement date. If CPI is less than 1, you are spending more than anticipated for the work completed at the measurement date.
The cost performance index (CPI) is calculated this way:
CPI = EV / AC
Plug in the numbers to see where you stand:
70,000 / 71,000 = .99

Since the result is less than one, it means cost performance is worse than expected.
The schedule performance index (SPI) measures the progress to date against the
progress that was planned. This formula should be used in conjunction with an analysis of the critical path activities to determine whether the project will fi nish ahead of or behind schedule. If SPI is greater than 1, your performance is better than expected, and you’re ahead of schedule. If SPI is less than 1, you ’ re behind schedule at the measurement date.