Thats incorrect (in the article). The words are compound words, and they really should not be counted like they are here.
example:
chauntees = 34 = 30 and 4. Word for 30 is tees and word for 4 is char - combined to form chaun-tees.
chhuttees = 36 = 30 and 6. Word for 30 is tees and word for 6 is chey - combined to form chhut-tees.
So on for all the words from 20 till 99. The combination rules might not be obvious here in transcription, but they come naturally to a Hindi speaker. So in reality there are dedicated words for 1 thru 19, and then the rest are compounds formed from the words corresponding to each digit.
example:
chauntees = 34 = 30 and 4. Word for 30 is tees and word for 4 is char - combined to form chaun-tees.
chhuttees = 36 = 30 and 6. Word for 30 is tees and word for 6 is chey - combined to form chhut-tees.
So on for all the words from 20 till 99. The combination rules might not be obvious here in transcription, but they come naturally to a Hindi speaker. So in reality there are dedicated words for 1 thru 19, and then the rest are compounds formed from the words corresponding to each digit.