223k views
0 votes
The value of the 8th term is 78 the sequence is increasing by 10 each time. find the 20th term

User Chapman
by
8.6k points

1 Answer

1 vote
an = a + (n - 1)d
a8 = a + (8 - 1) x 10 = a + 7 x 10 = a + 70
a + 70 = 78
a = 78 - 70 = 8

20th term (a20) = 8 + (20 - 1) x 10 = 8 + 19 x 10 = 8 + 190 = 198
User Martinaut
by
7.6k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories