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Finding the Fourth Proportional to 399.40, 596.12 and 389.68

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Solution

The fourth proportional to 399.40, 596.12 and 389.68 is: 581.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.40 : 596.12 = 389.68 : x
  2. Step 2: Convert to fraction form
    399.40/596.12 = 389.68/x
  3. Step 3: Cross multiply
    399.40x = 596.12 × 389.68
  4. Step 4: Simplify right side
    399.40x = 232,296.04
  5. Step 5: Solve for x
    x = 232,296.04/399.40
  6. Step 6: Final answer
    x = 581.61

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.