Yozhov spoke quickly and in a ringing voice: "Now we know that the first peddler made 17k.

profit." "Enough! Gordyeeff! Tell me what must we do in order to find out how much the second peddler gained ?" Watching the conduct of the boys, so unlike each other, Foma was thus taken unawares by the question and he kept quiet.
"Don't you know?
How?
Explain it to him, Smolin." Having carefully wiped his fingers, which had been soiled with chalk, Smolin put the rag away, and, without looking at Foma, finished the problem and again began to wipe his hands, while Yozhov, smiling and skipping along as he walked, returned to his seat.
"Eh, you!" he whispered, seating himself beside Foma, incidentally striking his side with his fist.

"Why don't you know it?
What was the profit altogether?
Thirty kopecks.

And there were two peddlers.

One of them got 17.