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Finding the Fourth Proportional to 103.20, 155.12 and 76.32

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Solution

The fourth proportional to 103.20, 155.12 and 76.32 is: 114.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.20 : 155.12 = 76.32 : x
  2. Step 2: Convert to fraction form
    103.20/155.12 = 76.32/x
  3. Step 3: Cross multiply
    103.20x = 155.12 × 76.32
  4. Step 4: Simplify right side
    103.20x = 11,838.76
  5. Step 5: Solve for x
    x = 11,838.76/103.20
  6. Step 6: Final answer
    x = 114.72

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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.