Asked by sdgsd
An arithmetic series has third term 11. The ninth term is 5 times the second term. Find the common difference.
Answers
Answered by
drwls
Let the first term be called a and the common difference be called b.
a + 2b = 11
a + 8b = 5*(a + b) = 5a + 5b
The last equation can be rewritten
4a - 3b = 0
4a + 8b = 44
11b = 44
b = 4
a = 11 - 2b = 3
The series is 3,7,11,15,19,23,27,31,35...
Note that 35 (the ninth term) is 5 times 7
a + 2b = 11
a + 8b = 5*(a + b) = 5a + 5b
The last equation can be rewritten
4a - 3b = 0
4a + 8b = 44
11b = 44
b = 4
a = 11 - 2b = 3
The series is 3,7,11,15,19,23,27,31,35...
Note that 35 (the ninth term) is 5 times 7
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.