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Finding the Fourth Proportional to 400.38, 596.78 and 389.40

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Solution

The fourth proportional to 400.38, 596.78 and 389.40 is: 580.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.38 : 596.78 = 389.40 : x
  2. Step 2: Convert to fraction form
    400.38/596.78 = 389.40/x
  3. Step 3: Cross multiply
    400.38x = 596.78 × 389.40
  4. Step 4: Simplify right side
    400.38x = 232,384.19
  5. Step 5: Solve for x
    x = 232,384.19/400.38
  6. Step 6: Final answer
    x = 580.41

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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.