On the first day of school, Mr. Vilani gave his third- grade students 5 new words to spell. On each day of school after that, he gave the students 3 new words to spell. In the first 20 days of school, how many new words had he given the students to spell?

So, the best way to solve this problem is by creating a equation for which we can substitute any number of days. For this problem that equation would be W=5+3(t-1)
W=number of words
T=time or number of days
-1= This is here because we are already accounting for the first day of school so we need to have 1 less day than the number of days they have been in school.
So in 20 days the students had received
5+3(19) or 62words.
62 words