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Finding the Fourth Proportional to 511.39, 766.82 and 280.21

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Solution

The fourth proportional to 511.39, 766.82 and 280.21 is: 420.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.39 : 766.82 = 280.21 : x
  2. Step 2: Convert to fraction form
    511.39/766.82 = 280.21/x
  3. Step 3: Cross multiply
    511.39x = 766.82 × 280.21
  4. Step 4: Simplify right side
    511.39x = 214,865.40
  5. Step 5: Solve for x
    x = 214,865.40/511.39
  6. Step 6: Final answer
    x = 420.16

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.