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Finding the Fourth Proportional to 257.78, 355.38 and 170.30

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Solution

The fourth proportional to 257.78, 355.38 and 170.30 is: 234.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.78 : 355.38 = 170.30 : x
  2. Step 2: Convert to fraction form
    257.78/355.38 = 170.30/x
  3. Step 3: Cross multiply
    257.78x = 355.38 × 170.30
  4. Step 4: Simplify right side
    257.78x = 60,521.21
  5. Step 5: Solve for x
    x = 60,521.21/257.78
  6. Step 6: Final answer
    x = 234.78

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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.