When searching for a specific height in the imperial system (such as 5 feet 4 inches, or variations like 5 ft 4 in), a Kagi widget activates and tries to "solve" this height. I'm not sure how it does it but it outputs 240 in² (see screenshots).
I would think unit conversion is among the most straightforward queries to handle. All search results for this query are already conversions to cm (as is the Quick Answer), implying that's overwhelmingly the reason to search for a ft/in height. And you will get a conversion widget activate for a query like "5 feet 4 inches in cm".
The same goes for temperature: query "98 fahrenheit" doesn't activate a widget, "98 fahrenheit in celsius" does. These aren't errors, but I would prefer if the default, most popular conversion activated for these extremely common cases, even without specifying the target unit. Same for MPa/atm, miles/km, psc/ly, in/cm, ft/m, yd/m, etc.
In any case, the math widget activating for X feet N inches is almost surely an error — I really don't know how you could solve that.
