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Finding the Fourth Proportional to 506.61, 699.71 and 391.05

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Solution

The fourth proportional to 506.61, 699.71 and 391.05 is: 540.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    506.61 : 699.71 = 391.05 : x
  2. Step 2: Convert to fraction form
    506.61/699.71 = 391.05/x
  3. Step 3: Cross multiply
    506.61x = 699.71 × 391.05
  4. Step 4: Simplify right side
    506.61x = 273,619.64
  5. Step 5: Solve for x
    x = 273,619.64/506.61
  6. Step 6: Final answer
    x = 540.10

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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.