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Finding the Fourth Proportional to 638.69, 958.43 and 378.47

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Solution

The fourth proportional to 638.69, 958.43 and 378.47 is: 567.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.69 : 958.43 = 378.47 : x
  2. Step 2: Convert to fraction form
    638.69/958.43 = 378.47/x
  3. Step 3: Cross multiply
    638.69x = 958.43 × 378.47
  4. Step 4: Simplify right side
    638.69x = 362,740.34
  5. Step 5: Solve for x
    x = 362,740.34/638.69
  6. Step 6: Final answer
    x = 567.95

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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.