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Finding the Fourth Proportional to 378.00, 520.85 and 289.47

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Solution

The fourth proportional to 378.00, 520.85 and 289.47 is: 398.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.00 : 520.85 = 289.47 : x
  2. Step 2: Convert to fraction form
    378.00/520.85 = 289.47/x
  3. Step 3: Cross multiply
    378.00x = 520.85 × 289.47
  4. Step 4: Simplify right side
    378.00x = 150,770.45
  5. Step 5: Solve for x
    x = 150,770.45/378.00
  6. Step 6: Final answer
    x = 398.87

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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.