logically fit together (This phrasal verb is often negative.)
find the total
zgadzać się, potwierdzać, trzymać się kupy;
zsumować, dodać ;
"His theory is hard to believe, but his research adds up."
"His theory seems, at first, to be plausible, but the facts in his research don't add up."
"What's the total of those bills? Could you add them up and see?"