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Finding the Fourth Proportional to 386.72, 580.14 and 130.28

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Solution

The fourth proportional to 386.72, 580.14 and 130.28 is: 195.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.72 : 580.14 = 130.28 : x
  2. Step 2: Convert to fraction form
    386.72/580.14 = 130.28/x
  3. Step 3: Cross multiply
    386.72x = 580.14 × 130.28
  4. Step 4: Simplify right side
    386.72x = 75,580.64
  5. Step 5: Solve for x
    x = 75,580.64/386.72
  6. Step 6: Final answer
    x = 195.44

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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.