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Finding the Fourth Proportional to 499.37, 689.31 and 389.61

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Solution

The fourth proportional to 499.37, 689.31 and 389.61 is: 537.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.37 : 689.31 = 389.61 : x
  2. Step 2: Convert to fraction form
    499.37/689.31 = 389.61/x
  3. Step 3: Cross multiply
    499.37x = 689.31 × 389.61
  4. Step 4: Simplify right side
    499.37x = 268,562.07
  5. Step 5: Solve for x
    x = 268,562.07/499.37
  6. Step 6: Final answer
    x = 537.81

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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.