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Finding the Fourth Proportional to 639.66, 959.49 and 628.74

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Solution

The fourth proportional to 639.66, 959.49 and 628.74 is: 943.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.66 : 959.49 = 628.74 : x
  2. Step 2: Convert to fraction form
    639.66/959.49 = 628.74/x
  3. Step 3: Cross multiply
    639.66x = 959.49 × 628.74
  4. Step 4: Simplify right side
    639.66x = 603,269.74
  5. Step 5: Solve for x
    x = 603,269.74/639.66
  6. Step 6: Final answer
    x = 943.11

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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.