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Finding the Fourth Proportional to 515.30, 771.41 and 339.80

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Solution

The fourth proportional to 515.30, 771.41 and 339.80 is: 508.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.30 : 771.41 = 339.80 : x
  2. Step 2: Convert to fraction form
    515.30/771.41 = 339.80/x
  3. Step 3: Cross multiply
    515.30x = 771.41 × 339.80
  4. Step 4: Simplify right side
    515.30x = 262,122.11
  5. Step 5: Solve for x
    x = 262,122.11/515.30
  6. Step 6: Final answer
    x = 508.68

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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.