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Finding the Fourth Proportional to 339.98, 509.36 and 257.56

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Solution

The fourth proportional to 339.98, 509.36 and 257.56 is: 385.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.98 : 509.36 = 257.56 : x
  2. Step 2: Convert to fraction form
    339.98/509.36 = 257.56/x
  3. Step 3: Cross multiply
    339.98x = 509.36 × 257.56
  4. Step 4: Simplify right side
    339.98x = 131,186.93
  5. Step 5: Solve for x
    x = 131,186.93/339.98
  6. Step 6: Final answer
    x = 385.87

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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.