Answer: 4
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Step-by-step explanation:
tells us that the third term is 6.25
The common ratio r = 5/4 = 1.25 tells us how to get the next term. We multiply the third term by 1.25 to get the next term
4th term = (3rd term)*(r) = (6.25)*(1.25) = 7.8125
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To go backwards and find the second term, we will divide by r, which is the inverse operation of multiplication.
2nd term = (3rd term)/r = (6.25)/(1.25) = 5
Use the same idea to find the 1st term
1st term = (2nd term)/r = 5/(1.25) = 4 is the final answer