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Finding the Fourth Proportional to 387.07, 580.40 and 130.39

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Solution

The fourth proportional to 387.07, 580.40 and 130.39 is: 195.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.07 : 580.40 = 130.39 : x
  2. Step 2: Convert to fraction form
    387.07/580.40 = 130.39/x
  3. Step 3: Cross multiply
    387.07x = 580.40 × 130.39
  4. Step 4: Simplify right side
    387.07x = 75,677.70
  5. Step 5: Solve for x
    x = 75,677.70/387.07
  6. Step 6: Final answer
    x = 195.51

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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.