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Finding the Fourth Proportional to 311.00, 428.83 and 258.38

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Solution

The fourth proportional to 311.00, 428.83 and 258.38 is: 356.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.00 : 428.83 = 258.38 : x
  2. Step 2: Convert to fraction form
    311.00/428.83 = 258.38/x
  3. Step 3: Cross multiply
    311.00x = 428.83 × 258.38
  4. Step 4: Simplify right side
    311.00x = 110,798.31
  5. Step 5: Solve for x
    x = 110,798.31/311.00
  6. Step 6: Final answer
    x = 356.27

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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.