Question

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

Answer 1

Answer:

The common difference (or common ratio) = 0.75

Step-by-step 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 = $\frac{60}{80}$ = 0.75

iii) let the third term be     $a_{3}$  = $a_{2}$ . r = 60 × r = 45      ∴  r = $\frac{45}{60}$ = 0.75

iv) let the fourth term be   $a_{4}$ = $a_{3}$ . r = 45 × r = 33.75   ∴ r = $\frac{33.75}{45}$ = 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.