7.4. Karlson counts 200 buns baked by Fräulein Bock: «one, two, three, ..., one hundred and nine, one hundred and ten, two hundred». How many words will he say in total? (Each word is counted as many times as it was said.)
Answer. 443 words.

Solution. One word is required to pronounce 29 numbers: $1,2,3,4,5,6,7,8,9,10,11,12$, $13,14,15,16,17,18,19,20,30,40,50,60,70,80,90,100,200$.

Among the first 99 numbers, the number of those pronounced in two words: $99-27=72$, thus, the number of words required for their pronunciation is $2 \cdot 72=144$.

In the next hundred (from 101 to 199), each number that is pronounced in one word in the first hundred will be pronounced in two, and the number of words is: $2 \cdot 27=54$. The rest are pronounced in three words: 3 . $(99-27)=216$.

Thus, to count all the buns, $29+144+54+216=443$ words will be needed.

## Criteria.

1 point. The number of numbers pronounced in one word is found reasonably.

2 points. The number of words required to pronounce numbers from 1 to 99 is found correctly and reasonably.

2 points. The number of words required to pronounce numbers from 100 to 199 or 200 is found correctly and reasonably.

Comment. Points according to the criteria above are summed up.

3 points. The correct answer without reasoning.