Faced with a financial crisis, Upland University’s board of trustees reduced the budget for the university’s computer center from last year’s $4 million to $1.5 million for the coming year.
Conclusion
There is no way that the center can be kept operating for the coming year.
Evidence (since)
The center cannot operate on less than $2.5 million.
The budget has been reduced from last year's $4 million to $1.5 million.
The board cannot divert funds from other programs to the computer center.
Evaluate
We're trying to prove that the center can't be kept operating for this year. Were we given some proving mechanism that allows us to say "thus, can't operate this year"?
Yes. We were told that the center can't operate on less than $2.5 million.
So in order to prove the conclusion, we have to establish that the center has less than $2.5 million.
The evidence tried to establish that by saying that the budget this year is only $1.5 million, and funds can't be diverted from other programs.
But does that guarantee that the center has less than $2.5 million?
What if they saved $1 million from last year? If they were given $4 million the previous year (and only need $2.5 million to operate), maybe they had a surplus that is still in their account.
What if they have a bake sale and raise $1 million?
Goal
We need to be convinced that they have less than $2.5 million, so the correct answer should rule out the possibility that they can supplement the $1.5 million they're budgeted with extra money from some other source.