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Finding the Fourth Proportional to 638.98, 958.56 and 636.64

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Solution

The fourth proportional to 638.98, 958.56 and 636.64 is: 955.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.98 : 958.56 = 636.64 : x
  2. Step 2: Convert to fraction form
    638.98/958.56 = 636.64/x
  3. Step 3: Cross multiply
    638.98x = 958.56 × 636.64
  4. Step 4: Simplify right side
    638.98x = 610,257.64
  5. Step 5: Solve for x
    x = 610,257.64/638.98
  6. Step 6: Final answer
    x = 955.05

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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.