Step-by-step explanation:
The graph is shown in the image above.
30 miles is two-thirds of x (where x is the total distance)
<span>30 = (2/3)*x </span>
<span>30*3 = 2x
</span><span><span>90 = 2x
90/2 = x
45 = x
x = 45
The total length of his drive is 45 miles</span><span>
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Answer:
You shoud invest $0.204, it is an small amount each month.
The formula to calculate the monthly saving is

with PP: periodic payments, A: amount desired, n: number of payments in one year, Y: number of years.
In this case A = 88, n= 12 (the payments are monthly), Y=18, APR=7%.
Replacing in the formula you obtain that 
10 is the greatest common factor if two or more numbers