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Finding the Third Proportional to 1,380 and 1,680

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Solution

The third proportional to 1,380 and 1,680 is: 2,045.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380 : 1,680 = 1,680 : x
  2. Step 2: Convert to fraction form
    1,380/1,680 = 1,680/x
  3. Step 3: Cross multiply
    1,380x = 1,680 × 1,680
  4. Step 4: Simplify right side
    1,380x = 2,822,400
  5. Step 5: Solve for x
    x = 2,822,400/1,380
  6. Step 6: Final answer
    x = 2,045.22

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Why These Related Problems?

These problems maintain the same ratio (1.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.