The number of gallons this well will produce before it runs out is 1.789 x 10⁷ gallons.
The given parameters;
The number of gallons this well will produce before it runs out is calculated from sum of sequence.
The sum of barrels produced is calculated as;
[tex]s_n = \frac{a}{1-r} = \frac{426}{1-0.999} = 426,000 \ barrels[/tex]
The equivalent of this barrels in gallons is calculated as;
[tex]= 426,000 \ barrels\ \times \frac{42 \ gallons}{barrel} \\\\= 1.789 \times 10^{7} \ gallons[/tex]
Thus, the number of gallons this well will produce before it runs out is 1.789 x 10⁷ gallons.
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