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There are two sets A and B each of which consists of three numbers in GP whose product is 64 and R and r are the common ratios sich that `R=r+2`. If `(p)/(q)=(3)/(2)`, where p and q are sum of numbers taken two at a time respectively in the two sets.
The value of q is

A

54

B

56

C

58

D

60

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To solve the problem, we need to follow these steps: ### Step 1: Understand the Given Information We have two sets A and B, each consisting of three numbers in a geometric progression (GP). The product of the numbers in each set is 64. The common ratios for sets A and B are denoted as R and r, respectively, with the relationship \( R = r + 2 \). ### Step 2: Express the Numbers in GP Let the three numbers in set A be: - \( a/r \) - \( a \) - \( ar \) The product of these numbers is given by: \[ \frac{a}{r} \cdot a \cdot ar = a^3 = 64 \] Thus, we find: \[ a = 4 \] ### Step 3: Find the Common Ratios Now, substituting \( a = 4 \) into the expressions for the numbers in set A, we have: - \( \frac{4}{R} \) - \( 4 \) - \( 4R \) For set B, the numbers will be: - \( \frac{4}{r} \) - \( 4 \) - \( 4r \) ### Step 4: Calculate P and Q Now, we calculate \( P \) and \( Q \), where \( P \) is the sum of products taken two at a time from set A: \[ P = \left(\frac{4}{R} \cdot 4\right) + \left(4 \cdot 4R\right) + \left(\frac{4}{R} \cdot 4R\right) = \frac{16}{R} + 16R + 16 \] Similarly, for set B: \[ Q = \left(\frac{4}{r} \cdot 4\right) + \left(4 \cdot 4r\right) + \left(\frac{4}{r} \cdot 4r\right) = \frac{16}{r} + 16r + 16 \] ### Step 5: Set Up the Ratio According to the problem, we have: \[ \frac{P}{Q} = \frac{3}{2} \] Substituting the expressions for \( P \) and \( Q \): \[ \frac{\frac{16}{R} + 16R + 16}{\frac{16}{r} + 16r + 16} = \frac{3}{2} \] ### Step 6: Simplify the Equation We can simplify the equation by multiplying both sides by \( 2 \left(\frac{16}{r} + 16r + 16\right) \): \[ 2\left(\frac{16}{R} + 16R + 16\right) = 3\left(\frac{16}{r} + 16r + 16\right) \] ### Step 7: Substitute R in Terms of r Since \( R = r + 2 \), we can substitute \( R \) in the equation: \[ 2\left(\frac{16}{r + 2} + 16(r + 2) + 16\right) = 3\left(\frac{16}{r} + 16r + 16\right) \] ### Step 8: Solve the Equation After substituting and simplifying, we will arrive at a cubic equation in terms of \( r \): \[ r^3 + 5r^2 - 7r = 0 \] Factoring gives us: \[ (r - 2)(r^2 + 7r + 3) = 0 \] Thus, \( r = 2 \) is a solution. ### Step 9: Find the Value of Q Substituting \( r = 2 \) back into the expression for \( Q \): \[ Q = \frac{16}{2} + 16(2) + 16 = 8 + 32 + 16 = 56 \] Thus, the value of \( q \) is: \[ \boxed{56} \]

To solve the problem, we need to follow these steps: ### Step 1: Understand the Given Information We have two sets A and B, each consisting of three numbers in a geometric progression (GP). The product of the numbers in each set is 64. The common ratios for sets A and B are denoted as R and r, respectively, with the relationship \( R = r + 2 \). ### Step 2: Express the Numbers in GP Let the three numbers in set A be: - \( a/r \) ...
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