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Finding the Fourth Proportional to 501.40, 691.91 and 280.35

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Solution

The fourth proportional to 501.40, 691.91 and 280.35 is: 386.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.40 : 691.91 = 280.35 : x
  2. Step 2: Convert to fraction form
    501.40/691.91 = 280.35/x
  3. Step 3: Cross multiply
    501.40x = 691.91 × 280.35
  4. Step 4: Simplify right side
    501.40x = 193,976.97
  5. Step 5: Solve for x
    x = 193,976.97/501.40
  6. Step 6: Final answer
    x = 386.87

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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.