In each term of a sequence, 9 is added to get the next term. If the first term is 2, what is the eighty-first term?  Choose the correct choice
A) 632 B) 695 C) 713 D) 722 E) 731
Let’s think about the first few terms of this sequence.   a_1=2   a_2=11 = 2 + 9   a_3=20 = 2 + 9 + 9   a_4=29 = 2 + 9 + 9 + 9   To find each new term, we add 9. The result is, each term equals 2 plus a sum of 9’s. How many nines? Well, the second term has one 9, the third term has two 9’s, the fourth term has three 9’s, so it’s clear the nth term would have a sum of (n – 1) 9’s. Thus, the eighty-first term would be 2 plus eighty 9’s. Well, eighty 9’s = 80*9= 
<gadget id="calculator">80*9</gadget>
<output>720</output>
720, so the eighty-first term= 722, answer 722.
<result>D</result>
In each term of a sequence, 9 is added to get the next term. If the first term is 2, what is the eighty-first term?