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Finding the Fourth Proportional to 257.82, 355.78 and 139.79

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Solution

The fourth proportional to 257.82, 355.78 and 139.79 is: 192.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.82 : 355.78 = 139.79 : x
  2. Step 2: Convert to fraction form
    257.82/355.78 = 139.79/x
  3. Step 3: Cross multiply
    257.82x = 355.78 × 139.79
  4. Step 4: Simplify right side
    257.82x = 49,733.98
  5. Step 5: Solve for x
    x = 49,733.98/257.82
  6. Step 6: Final answer
    x = 192.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.