What is the explicit formula for the arithmetic sequence 4/5, 29/30, 17/15, 13/10. Answer is D on Edg an = 4/5 + 1/6(n-1)

Question

asked Oct 28, 2020 25.2k views

2 Answers

Pardeep Poria · Answer 1 · 2020-11-02T10:36:12+0000

Answer:

a_n=(4)/(5)+(1)/(6)(n-1)

Explanation:

The explicit formula is given by:

a_n=a+(n-1)d

Where a is the first term (4/5) and d is the common difference (the difference is any 2 terms). So to find d:

29/30 - 4/5

29/30 - 24/30

5/30

1/6

d = 1/6

Now putting them into the formula:

$a_n=a+(n-1)d\\a_n=(4)/(5)+(n-1)*(1)/(6)$

The last answer choice is right.