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Finding the Fourth Proportional to 619.78, 855.26 and 339.98

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Solution

The fourth proportional to 619.78, 855.26 and 339.98 is: 469.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.78 : 855.26 = 339.98 : x
  2. Step 2: Convert to fraction form
    619.78/855.26 = 339.98/x
  3. Step 3: Cross multiply
    619.78x = 855.26 × 339.98
  4. Step 4: Simplify right side
    619.78x = 290,771.29
  5. Step 5: Solve for x
    x = 290,771.29/619.78
  6. Step 6: Final answer
    x = 469.15

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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.