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Finding the Third Proportional to 7,680 and 8,640

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Solution

The third proportional to 7,680 and 8,640 is: 9,720

Step by Step Solution

  1. Step 1: Write the proportion equation
    7,680 : 8,640 = 8,640 : x
  2. Step 2: Convert to fraction form
    7,680/8,640 = 8,640/x
  3. Step 3: Cross multiply
    7,680x = 8,640 × 8,640
  4. Step 4: Simplify right side
    7,680x = 74,649,600
  5. Step 5: Solve for x
    x = 74,649,600/7,680
  6. Step 6: Final answer
    x = 9,720

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Why These Related Problems?

These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.