The sum of the first n terms in a geometric sequence given the first term (a1) and the common ratio (r) is calculated through the equation,
<span>Sn </span>= (<span><span><span>a1</span>(1−<span>r^n</span>) / (</span><span>1−r)
Substituting the known terms,
Sn = (20)(1 - (1/4)^4)) / (1 - 1/4)
Sn = 26.5625
Thus, the sum of the first four terms is 26.5625. </span></span>
I think the answer is A. 20 inches^2. sorry if it’s wrong
The area of the fence is 6*25=150 square feet.
It will take him 150 / 2 = 75 of 10-minute intervals. 75 min *10 = 750 min = 750/60 hours = 12.5 hours.
I believe it would b A. Hope it helps
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