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Finding the Fourth Proportional to 501.21, 691.65 and 280.12

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Solution

The fourth proportional to 501.21, 691.65 and 280.12 is: 386.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.21 : 691.65 = 280.12 : x
  2. Step 2: Convert to fraction form
    501.21/691.65 = 280.12/x
  3. Step 3: Cross multiply
    501.21x = 691.65 × 280.12
  4. Step 4: Simplify right side
    501.21x = 193,745.00
  5. Step 5: Solve for x
    x = 193,745.00/501.21
  6. Step 6: Final answer
    x = 386.55

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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.