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Finding the Fourth Proportional to 378.82, 522.09 and 280.41

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Solution

The fourth proportional to 378.82, 522.09 and 280.41 is: 386.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.82 : 522.09 = 280.41 : x
  2. Step 2: Convert to fraction form
    378.82/522.09 = 280.41/x
  3. Step 3: Cross multiply
    378.82x = 522.09 × 280.41
  4. Step 4: Simplify right side
    378.82x = 146,398.35
  5. Step 5: Solve for x
    x = 146,398.35/378.82
  6. Step 6: Final answer
    x = 386.46

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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.