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Finding the Fourth Proportional to 639.58, 959.13 and 228.61

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Solution

The fourth proportional to 639.58, 959.13 and 228.61 is: 342.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.58 : 959.13 = 228.61 : x
  2. Step 2: Convert to fraction form
    639.58/959.13 = 228.61/x
  3. Step 3: Cross multiply
    639.58x = 959.13 × 228.61
  4. Step 4: Simplify right side
    639.58x = 219,264.31
  5. Step 5: Solve for x
    x = 219,264.31/639.58
  6. Step 6: Final answer
    x = 342.83

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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.