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Finding the Fourth Proportional to 639.50, 958.95 and 379.54

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Solution

The fourth proportional to 639.50, 958.95 and 379.54 is: 569.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.50 : 958.95 = 379.54 : x
  2. Step 2: Convert to fraction form
    639.50/958.95 = 379.54/x
  3. Step 3: Cross multiply
    639.50x = 958.95 × 379.54
  4. Step 4: Simplify right side
    639.50x = 363,959.88
  5. Step 5: Solve for x
    x = 363,959.88/639.50
  6. Step 6: Final answer
    x = 569.13

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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.