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Finding the Fourth Proportional to 639.48, 958.68 and 378.84

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Solution

The fourth proportional to 639.48, 958.68 and 378.84 is: 567.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.48 : 958.68 = 378.84 : x
  2. Step 2: Convert to fraction form
    639.48/958.68 = 378.84/x
  3. Step 3: Cross multiply
    639.48x = 958.68 × 378.84
  4. Step 4: Simplify right side
    639.48x = 363,186.33
  5. Step 5: Solve for x
    x = 363,186.33/639.48
  6. Step 6: Final answer
    x = 567.94

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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.