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Finding the Fourth Proportional to 407.70, 611.55 and 339.30

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Solution

The fourth proportional to 407.70, 611.55 and 339.30 is: 508.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.70 : 611.55 = 339.30 : x
  2. Step 2: Convert to fraction form
    407.70/611.55 = 339.30/x
  3. Step 3: Cross multiply
    407.70x = 611.55 × 339.30
  4. Step 4: Simplify right side
    407.70x = 207,498.92
  5. Step 5: Solve for x
    x = 207,498.92/407.70
  6. Step 6: Final answer
    x = 508.95

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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.