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Finding the Fourth Proportional to 392.07, 540.42 and 307.89

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Solution

The fourth proportional to 392.07, 540.42 and 307.89 is: 424.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.07 : 540.42 = 307.89 : x
  2. Step 2: Convert to fraction form
    392.07/540.42 = 307.89/x
  3. Step 3: Cross multiply
    392.07x = 540.42 × 307.89
  4. Step 4: Simplify right side
    392.07x = 166,389.91
  5. Step 5: Solve for x
    x = 166,389.91/392.07
  6. Step 6: Final answer
    x = 424.39

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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.