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Finding the Fourth Proportional to 412.39, 617.80 and 206.72

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Solution

The fourth proportional to 412.39, 617.80 and 206.72 is: 309.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.39 : 617.80 = 206.72 : x
  2. Step 2: Convert to fraction form
    412.39/617.80 = 206.72/x
  3. Step 3: Cross multiply
    412.39x = 617.80 × 206.72
  4. Step 4: Simplify right side
    412.39x = 127,711.62
  5. Step 5: Solve for x
    x = 127,711.62/412.39
  6. Step 6: Final answer
    x = 309.69

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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.