Answer: 
<u>Step-by-step explanation:</u>
a₁, 375, a₃, a₄, 81
First, let's find the ratio (r). There are three multiple from 375 to 81.
![375r^3=81\\\\r^3=\dfrac{81}{375}\\\\\\r^3=\dfrac{27}{125}\qquad \leftarrow simplied\\\\\\\sqrt[3]{r^3} =\sqrt[3]{\dfrac{27}{125}}\\ \\\\r=\dfrac{3}{5}](https://tex.z-dn.net/?f=375r%5E3%3D81%5C%5C%5C%5Cr%5E3%3D%5Cdfrac%7B81%7D%7B375%7D%5C%5C%5C%5C%5C%5Cr%5E3%3D%5Cdfrac%7B27%7D%7B125%7D%5Cqquad%20%5Cleftarrow%20simplied%5C%5C%5C%5C%5C%5C%5Csqrt%5B3%5D%7Br%5E3%7D%20%3D%5Csqrt%5B3%5D%7B%5Cdfrac%7B27%7D%7B125%7D%7D%5C%5C%20%5C%5C%5C%5Cr%3D%5Cdfrac%7B3%7D%7B5%7D)
Next, let's find a₁

Lastly, Use the Infinite Geometric Sum Formula to find the sum:

I think it is 1.5, sorry if i'm wrong good luck!!!
:)
Answer:
Where's the figure,my friend?
The length of eastern continental trail is 5400 miles and length of erie canal trail is 360 miles.
Step-by-step explanation:
Given,
Combined length of both trails = 5760 miles
Let,
x be the length of eatern continental trail.
y be the length of Erie canal trail.
According to given statement;
x+y=5760 Eqn 1
x = 15y Eqn 2
Putting value of x from Eqn 2 in Eqn 1

Dividing both sides by 16

Putting y=360 in Eqn 2

The length of eastern continental trail is 5400 miles and length of erie canal trail is 360 miles.
Keywords: linear equation, substitution method
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