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Finding the Fourth Proportional to 280.78, 418.56 and 265.39

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Solution

The fourth proportional to 280.78, 418.56 and 265.39 is: 395.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.78 : 418.56 = 265.39 : x
  2. Step 2: Convert to fraction form
    280.78/418.56 = 265.39/x
  3. Step 3: Cross multiply
    280.78x = 418.56 × 265.39
  4. Step 4: Simplify right side
    280.78x = 111,083.82
  5. Step 5: Solve for x
    x = 111,083.82/280.78
  6. Step 6: Final answer
    x = 395.62

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.