In a geometric sequence, the first term, a1, is equal to 8 , and the third term, a3, is equal to 200 . Which number represents the common ratio of the geometric sequence?r=3r=4r=5r=6
Q. In a geometric sequence, the first term, a1, is equal to 8 , and the third term, a3, is equal to 200 . Which number represents the common ratio of the geometric sequence?r=3r=4r=5r=6
Identify Given Terms: Identify the given terms in the geometric sequence.We are given the first term a1=8 and the third term a3=200. In a geometric sequence, each term after the first is found by multiplying the previous term by a constant called the common ratio (r).
Write Third Term Formula: Write the formula for the third term of a geometric sequence.The third term a3 can be found by multiplying the first term a1 by the common ratio (r) twice, since a3=a1×r2.
Substitute Known Values: Substitute the known values into the formula.We have a3=200 and a1=8, so we can write 200=8×r2.
Solve for Common Ratio: Solve for the common ratio r. Divide both sides of the equation by 8 to isolate r2. 8200=r225=r2
Find Value of r: Find the value of r by taking the square root of both sides.Since r2=25, we take the square root of 25 to find r.r=25r=5
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