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Finding the Fourth Proportional to 385.17, 577.72 and 211.78

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Solution

The fourth proportional to 385.17, 577.72 and 211.78 is: 317.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.17 : 577.72 = 211.78 : x
  2. Step 2: Convert to fraction form
    385.17/577.72 = 211.78/x
  3. Step 3: Cross multiply
    385.17x = 577.72 × 211.78
  4. Step 4: Simplify right side
    385.17x = 122,351.07
  5. Step 5: Solve for x
    x = 122,351.07/385.17
  6. Step 6: Final answer
    x = 317.65

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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.