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Finding the Fourth Proportional to 639.81, 960.62 and 628.86

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Solution

The fourth proportional to 639.81, 960.62 and 628.86 is: 944.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.81 : 960.62 = 628.86 : x
  2. Step 2: Convert to fraction form
    639.81/960.62 = 628.86/x
  3. Step 3: Cross multiply
    639.81x = 960.62 × 628.86
  4. Step 4: Simplify right side
    639.81x = 604,092.35
  5. Step 5: Solve for x
    x = 604,092.35/639.81
  6. Step 6: Final answer
    x = 944.17

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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.