How many numbers are in the list 147, 144, 141,... 42, 39?
so this means it skips 2 numbers each time and the numers between 147 and 39 are 119 so would i divide by 3?
We have this
Last term = First Term - 3(N - 1) where N is the number of terms
39 = 147 - 3(N - 1) simplfy
39 = 147 - 3N + 3
39 + 150 - 3N subtract 150 from both sides
-111 = -3N divide both sides by -3
37 = N (37 terms)
