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Finding the Fourth Proportional to 402.40, 603.64 and 389.60

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Solution

The fourth proportional to 402.40, 603.64 and 389.60 is: 584.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.40 : 603.64 = 389.60 : x
  2. Step 2: Convert to fraction form
    402.40/603.64 = 389.60/x
  3. Step 3: Cross multiply
    402.40x = 603.64 × 389.60
  4. Step 4: Simplify right side
    402.40x = 235,178.14
  5. Step 5: Solve for x
    x = 235,178.14/402.40
  6. Step 6: Final answer
    x = 584.44

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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.