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Finding the Fourth Proportional to 639.98, 955.27 and 638.36

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Solution

The fourth proportional to 639.98, 955.27 and 638.36 is: 952.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.98 : 955.27 = 638.36 : x
  2. Step 2: Convert to fraction form
    639.98/955.27 = 638.36/x
  3. Step 3: Cross multiply
    639.98x = 955.27 × 638.36
  4. Step 4: Simplify right side
    639.98x = 609,799.78
  5. Step 5: Solve for x
    x = 609,799.78/639.98
  6. Step 6: Final answer
    x = 952.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.