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Finding the Fourth Proportional to 372.05, 558.12 and 128.51

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Solution

The fourth proportional to 372.05, 558.12 and 128.51 is: 192.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    372.05 : 558.12 = 128.51 : x
  2. Step 2: Convert to fraction form
    372.05/558.12 = 128.51/x
  3. Step 3: Cross multiply
    372.05x = 558.12 × 128.51
  4. Step 4: Simplify right side
    372.05x = 71,724.00
  5. Step 5: Solve for x
    x = 71,724.00/372.05
  6. Step 6: Final answer
    x = 192.78

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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.