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Finding the Fourth Proportional to 403.90, 557.25 and 320.75

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Solution

The fourth proportional to 403.90, 557.25 and 320.75 is: 442.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.90 : 557.25 = 320.75 : x
  2. Step 2: Convert to fraction form
    403.90/557.25 = 320.75/x
  3. Step 3: Cross multiply
    403.90x = 557.25 × 320.75
  4. Step 4: Simplify right side
    403.90x = 178,737.94
  5. Step 5: Solve for x
    x = 178,737.94/403.90
  6. Step 6: Final answer
    x = 442.53

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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.