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Finding the Fourth Proportional to 654.78, 903.65 and 392.79

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Solution

The fourth proportional to 654.78, 903.65 and 392.79 is: 542.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.78 : 903.65 = 392.79 : x
  2. Step 2: Convert to fraction form
    654.78/903.65 = 392.79/x
  3. Step 3: Cross multiply
    654.78x = 903.65 × 392.79
  4. Step 4: Simplify right side
    654.78x = 354,944.68
  5. Step 5: Solve for x
    x = 354,944.68/654.78
  6. Step 6: Final answer
    x = 542.08

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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.