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Finding the Fourth Proportional to 639.53, 958.73 and 378.89

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Solution

The fourth proportional to 639.53, 958.73 and 378.89 is: 567.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.53 : 958.73 = 378.89 : x
  2. Step 2: Convert to fraction form
    639.53/958.73 = 378.89/x
  3. Step 3: Cross multiply
    639.53x = 958.73 × 378.89
  4. Step 4: Simplify right side
    639.53x = 363,246.52
  5. Step 5: Solve for x
    x = 363,246.52/639.53
  6. Step 6: Final answer
    x = 567.99

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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.