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Finding the Fourth Proportional to 506.60, 699.78 and 487.40

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Solution

The fourth proportional to 506.60, 699.78 and 487.40 is: 673.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    506.60 : 699.78 = 487.40 : x
  2. Step 2: Convert to fraction form
    506.60/699.78 = 487.40/x
  3. Step 3: Cross multiply
    506.60x = 699.78 × 487.40
  4. Step 4: Simplify right side
    506.60x = 341,072.77
  5. Step 5: Solve for x
    x = 341,072.77/506.60
  6. Step 6: Final answer
    x = 673.26

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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.