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Finding the Fourth Proportional to 386.07, 579.09 and 129.57

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Solution

The fourth proportional to 386.07, 579.09 and 129.57 is: 194.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.07 : 579.09 = 129.57 : x
  2. Step 2: Convert to fraction form
    386.07/579.09 = 129.57/x
  3. Step 3: Cross multiply
    386.07x = 579.09 × 129.57
  4. Step 4: Simplify right side
    386.07x = 75,032.69
  5. Step 5: Solve for x
    x = 75,032.69/386.07
  6. Step 6: Final answer
    x = 194.35

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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.