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Finding the Fourth Proportional to 285.77, 428.33 and 129.72

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Solution

The fourth proportional to 285.77, 428.33 and 129.72 is: 194.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.77 : 428.33 = 129.72 : x
  2. Step 2: Convert to fraction form
    285.77/428.33 = 129.72/x
  3. Step 3: Cross multiply
    285.77x = 428.33 × 129.72
  4. Step 4: Simplify right side
    285.77x = 55,564.90
  5. Step 5: Solve for x
    x = 55,564.90/285.77
  6. Step 6: Final answer
    x = 194.44

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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.