В школе заболела преподавательница русского языка и поставили...

A teacher of the Russian language fell ill at school and was replaced by a mathematician (M).
Well, then he comes to the lesson to the students (U).
M: What is the topic of the last task?
W: Cases.
M: Repeat cases:
Nominal: who, what.
Genitive: whom, what.
Dative: to whom ...? (writes on the blackboard)
who what
whom / what
to whom /?
M: And then who knows?
W: Do not remember (kidding).
M: Then we get it.
Let the unknown word X, then:
who what
whom / what
to whom / X
make up the proportion:
whom / what = to whom / X
(th) is reduced, we get:
co / che = com / x
similarly reduce (co), we obtain:
1 / che = mu / X
Multiply:
1 * X = Th * mu
We get:
X = what
U: ... ??? ... !!! ...
M: Let's move on. Creative: by whom, by what ...
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