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Finding the Fourth Proportional to 403.99, 605.31 and 388.81

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Solution

The fourth proportional to 403.99, 605.31 and 388.81 is: 582.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.99 : 605.31 = 388.81 : x
  2. Step 2: Convert to fraction form
    403.99/605.31 = 388.81/x
  3. Step 3: Cross multiply
    403.99x = 605.31 × 388.81
  4. Step 4: Simplify right side
    403.99x = 235,347.55
  5. Step 5: Solve for x
    x = 235,347.55/403.99
  6. Step 6: Final answer
    x = 582.56

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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.