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Finding the Fourth Proportional to 639.44, 956.66 and 485.81

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Solution

The fourth proportional to 639.44, 956.66 and 485.81 is: 726.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.44 : 956.66 = 485.81 : x
  2. Step 2: Convert to fraction form
    639.44/956.66 = 485.81/x
  3. Step 3: Cross multiply
    639.44x = 956.66 × 485.81
  4. Step 4: Simplify right side
    639.44x = 464,747.78
  5. Step 5: Solve for x
    x = 464,747.78/639.44
  6. Step 6: Final answer
    x = 726.81

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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.