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Finding the Fourth Proportional to 501.70, 692.39 and 280.72

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Solution

The fourth proportional to 501.70, 692.39 and 280.72 is: 387.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.70 : 692.39 = 280.72 : x
  2. Step 2: Convert to fraction form
    501.70/692.39 = 280.72/x
  3. Step 3: Cross multiply
    501.70x = 692.39 × 280.72
  4. Step 4: Simplify right side
    501.70x = 194,369.26
  5. Step 5: Solve for x
    x = 194,369.26/501.70
  6. Step 6: Final answer
    x = 387.42

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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.