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Finding the Fourth Proportional to 372.39, 558.57 and 128.91

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Solution

The fourth proportional to 372.39, 558.57 and 128.91 is: 193.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    372.39 : 558.57 = 128.91 : x
  2. Step 2: Convert to fraction form
    372.39/558.57 = 128.91/x
  3. Step 3: Cross multiply
    372.39x = 558.57 × 128.91
  4. Step 4: Simplify right side
    372.39x = 72,005.26
  5. Step 5: Solve for x
    x = 72,005.26/372.39
  6. Step 6: Final answer
    x = 193.36

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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.