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Finding the Fourth Proportional to 385.63, 578.48 and 129.13

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Solution

The fourth proportional to 385.63, 578.48 and 129.13 is: 193.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.63 : 578.48 = 129.13 : x
  2. Step 2: Convert to fraction form
    385.63/578.48 = 129.13/x
  3. Step 3: Cross multiply
    385.63x = 578.48 × 129.13
  4. Step 4: Simplify right side
    385.63x = 74,699.12
  5. Step 5: Solve for x
    x = 74,699.12/385.63
  6. Step 6: Final answer
    x = 193.71

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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.