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Finding the Fourth Proportional to 257.33, 385.81 and 120.30

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Solution

The fourth proportional to 257.33, 385.81 and 120.30 is: 180.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.33 : 385.81 = 120.30 : x
  2. Step 2: Convert to fraction form
    257.33/385.81 = 120.30/x
  3. Step 3: Cross multiply
    257.33x = 385.81 × 120.30
  4. Step 4: Simplify right side
    257.33x = 46,410.41
  5. Step 5: Solve for x
    x = 46,410.41/257.33
  6. Step 6: Final answer
    x = 180.36

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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.