Next two terms in sequence 1000,200,40

Question

I just still don't know how you got the answer

Answer 1

1000, 200, 40, ...

This is a geometric series with a common ratio of 1/5

Terms are found by the following:  a_n+1 = a_n/5

 

1000/5 = 200

200/5 = 40

40/5 = 8

8/5 = 1 3/5

(8/5)/5 = 8/25

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If asked to find the term prior to 1000 it would be 5,000

a_n+1 = a_n/5  so   a_n = 5(a_n+1)

Answer 2

1000/5 = 200

200/5 = 40

 

40/5 = 8

 

8/5 = 1 and 3/5