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Finding the Fourth Proportional to 730.21, 1,007.71 and 398.65

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Solution

The fourth proportional to 730.21, 1,007.71 and 398.65 is: 550.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    730.21 : 1,007.71 = 398.65 : x
  2. Step 2: Convert to fraction form
    730.21/1,007.71 = 398.65/x
  3. Step 3: Cross multiply
    730.21x = 1,007.71 × 398.65
  4. Step 4: Simplify right side
    730.21x = 401,723.59
  5. Step 5: Solve for x
    x = 401,723.59/730.21
  6. Step 6: Final answer
    x = 550.15

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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.