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Finding the Fourth Proportional to 721.82, 996.11 and 390.25

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Solution

The fourth proportional to 721.82, 996.11 and 390.25 is: 538.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.82 : 996.11 = 390.25 : x
  2. Step 2: Convert to fraction form
    721.82/996.11 = 390.25/x
  3. Step 3: Cross multiply
    721.82x = 996.11 × 390.25
  4. Step 4: Simplify right side
    721.82x = 388,731.52
  5. Step 5: Solve for x
    x = 388,731.52/721.82
  6. Step 6: Final answer
    x = 538.54

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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.