Question

What is the common difference of 80,60,45,33.75

Answer 1

The common difference (or common ratio) = 0.75

Explanation:

i) let the first term be
`a_(1)` = 80

ii) let the second term be
`a_(2)` =
`a_(1)` . r = 80 × r = 60 ∴ r =
`(60)/(80)` = 0.75

iii) let the third term be
`a_(3)` =
`a_(2)` . r = 60 × r = 45 ∴ r =
`(45)/(60)` = 0.75

iv) let the fourth term be
`a_(4)` =
`a_(3)` . r = 45 × r = 33.75 ∴ r =
`(33.75)/(45)` = 0.75

Therefore we can see that the series of numbers are part of a geometric progression and the first term is 80 and the common ratio = 0.75.