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Finding the Fourth Proportional to 501.39, 691.86 and 280.35

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Solution

The fourth proportional to 501.39, 691.86 and 280.35 is: 386.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.39 : 691.86 = 280.35 : x
  2. Step 2: Convert to fraction form
    501.39/691.86 = 280.35/x
  3. Step 3: Cross multiply
    501.39x = 691.86 × 280.35
  4. Step 4: Simplify right side
    501.39x = 193,962.95
  5. Step 5: Solve for x
    x = 193,962.95/501.39
  6. Step 6: Final answer
    x = 386.85

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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.