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Finding the Fourth Proportional to 475.20, 712.73 and 128.55

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Solution

The fourth proportional to 475.20, 712.73 and 128.55 is: 192.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    475.20 : 712.73 = 128.55 : x
  2. Step 2: Convert to fraction form
    475.20/712.73 = 128.55/x
  3. Step 3: Cross multiply
    475.20x = 712.73 × 128.55
  4. Step 4: Simplify right side
    475.20x = 91,621.44
  5. Step 5: Solve for x
    x = 91,621.44/475.20
  6. Step 6: Final answer
    x = 192.81

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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.