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Finding the Fourth Proportional to 64.89, 89.13 and 63.87

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Solution

The fourth proportional to 64.89, 89.13 and 63.87 is: 87.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    64.89 : 89.13 = 63.87 : x
  2. Step 2: Convert to fraction form
    64.89/89.13 = 63.87/x
  3. Step 3: Cross multiply
    64.89x = 89.13 × 63.87
  4. Step 4: Simplify right side
    64.89x = 5,692.73
  5. Step 5: Solve for x
    x = 5,692.73/64.89
  6. Step 6: Final answer
    x = 87.73

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.