Answer:
The common difference (or common ratio) = 0.75
Step-by-step explanation:
i) let the first term be [tex]a_{1}[/tex] = 80
ii) let the second term be [tex]a_{2}[/tex] = [tex]a_{1}[/tex] . r = 80 × r = 60 ∴ r = [tex]\frac{60}{80}[/tex] = 0.75
iii) let the third term be [tex]a_{3}[/tex] = [tex]a_{2}[/tex] . r = 60 × r = 45 ∴ r = [tex]\frac{45}{60}[/tex] = 0.75
iv) let the fourth term be [tex]a_{4}[/tex] = [tex]a_{3}[/tex] . r = 45 × r = 33.75 ∴ r = [tex]\frac{33.75}{45}[/tex] = 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.
