Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

In a geometric sequence, the first term, 
a_(1), is equal to 3 , and the third term, 
a_(3), is equal to 192 . Which number represents the common ratio of the geometric sequence?

r=6

r=7

r=8

r=9

In a geometric sequence, the first term, a1 a_{1} , is equal to 33 , and the third term, a3 a_{3} , is equal to 192192 . Which number represents the common ratio of the geometric sequence?\newliner=6 r=6 \newliner=7 r=7 \newliner=8 r=8 \newliner=9 r=9

Full solution

Q. In a geometric sequence, the first term, a1 a_{1} , is equal to 33 , and the third term, a3 a_{3} , is equal to 192192 . Which number represents the common ratio of the geometric sequence?\newliner=6 r=6 \newliner=7 r=7 \newliner=8 r=8 \newliner=9 r=9
  1. Identify Given Terms: Identify the given terms in the geometric sequence. We are given the first term a1=3a_{1} = 3 and the third term a3=192a_{3} = 192. In a geometric sequence, each term after the first is found by multiplying the previous term by a constant called the common ratio (rr).
  2. Write Third Term Formula: Write the formula for the third term of a geometric sequence.\newlineThe nnth term of a geometric sequence can be found using the formula an=a1rn1a_{n} = a_{1} \cdot r^{n-1}. For the third term, the formula is a3=a1r31=a1r2a_{3} = a_{1} \cdot r^{3-1} = a_{1} \cdot r^2.
  3. Substitute Known Values: Substitute the known values into the formula.\newlineWe know that a1=3a_{1} = 3 and a3=192a_{3} = 192, so we can substitute these values into the formula to find r2r^2.\newline192=3×r2192 = 3 \times r^2
  4. Solve for r2r^2: Solve for r2r^2.\newlineTo find r2r^2, we divide both sides of the equation by 33.\newliner2=1923r^2 = \frac{192}{3}\newliner2=64r^2 = 64
  5. Find Value of r: Find the value of r.\newlineSince r2=64r^2 = 64, we take the square root of both sides to solve for r.\newliner=64r = \sqrt{64}\newliner=8r = 8 or r=8r = -8
  6. Determine Appropriate Value: Determine the appropriate value of rr. In the context of a geometric sequence, the common ratio can be positive or negative. However, since we are given options for rr and they are all positive, we choose r=8r = 8 as the common ratio.

More problems from Evaluate two-variable equations: word problems