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Finding the Fourth Proportional to 103.29, 154.72 and 85.20

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Solution

The fourth proportional to 103.29, 154.72 and 85.20 is: 127.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.29 : 154.72 = 85.20 : x
  2. Step 2: Convert to fraction form
    103.29/154.72 = 85.20/x
  3. Step 3: Cross multiply
    103.29x = 154.72 × 85.20
  4. Step 4: Simplify right side
    103.29x = 13,182.14
  5. Step 5: Solve for x
    x = 13,182.14/103.29
  6. Step 6: Final answer
    x = 127.62

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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.