US Social Security survivor’s benefit—amount

Trying to help a widow plan for the future…

According to “Survivors Benefit Amount” (as I understand), she should get 100% of her late husband’s benefits and lose her smaller amount. In a phone interview with the local Social Security office, she was told 82.5%. But neither computes to the dollar amount she was told by the same person.

Am I right about the hundred percent, or are there factors that page does not disclose that could reduce it?

Update: I called the Social Security national line, and to my surprise was not on hold for an hour. Person told me that I was correct and did not know why the local person got it wrong. The deceased was 91; the widow is slightly younger.