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Finding the Fourth Proportional to 689.38, 951.28 and 409.54

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Solution

The fourth proportional to 689.38, 951.28 and 409.54 is: 565.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.38 : 951.28 = 409.54 : x
  2. Step 2: Convert to fraction form
    689.38/951.28 = 409.54/x
  3. Step 3: Cross multiply
    689.38x = 951.28 × 409.54
  4. Step 4: Simplify right side
    689.38x = 389,587.21
  5. Step 5: Solve for x
    x = 389,587.21/689.38
  6. Step 6: Final answer
    x = 565.13

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.