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Finding the Fourth Proportional to 418.20, 577.31 and 278.55

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Solution

The fourth proportional to 418.20, 577.31 and 278.55 is: 384.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.20 : 577.31 = 278.55 : x
  2. Step 2: Convert to fraction form
    418.20/577.31 = 278.55/x
  3. Step 3: Cross multiply
    418.20x = 577.31 × 278.55
  4. Step 4: Simplify right side
    418.20x = 160,809.70
  5. Step 5: Solve for x
    x = 160,809.70/418.20
  6. Step 6: Final answer
    x = 384.53

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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.