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Finding the Fourth Proportional to 385.66, 578.08 and 212.12

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Solution

The fourth proportional to 385.66, 578.08 and 212.12 is: 317.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.66 : 578.08 = 212.12 : x
  2. Step 2: Convert to fraction form
    385.66/578.08 = 212.12/x
  3. Step 3: Cross multiply
    385.66x = 578.08 × 212.12
  4. Step 4: Simplify right side
    385.66x = 122,622.33
  5. Step 5: Solve for x
    x = 122,622.33/385.66
  6. Step 6: Final answer
    x = 317.95

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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.