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Finding the Fourth Proportional to 479.98, 720.34 and 206.30

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Solution

The fourth proportional to 479.98, 720.34 and 206.30 is: 309.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.98 : 720.34 = 206.30 : x
  2. Step 2: Convert to fraction form
    479.98/720.34 = 206.30/x
  3. Step 3: Cross multiply
    479.98x = 720.34 × 206.30
  4. Step 4: Simplify right side
    479.98x = 148,606.14
  5. Step 5: Solve for x
    x = 148,606.14/479.98
  6. Step 6: Final answer
    x = 309.61

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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.