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Finding the Fourth Proportional to 85.25, 127.64 and 64.87

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Solution

The fourth proportional to 85.25, 127.64 and 64.87 is: 97.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.25 : 127.64 = 64.87 : x
  2. Step 2: Convert to fraction form
    85.25/127.64 = 64.87/x
  3. Step 3: Cross multiply
    85.25x = 127.64 × 64.87
  4. Step 4: Simplify right side
    85.25x = 8,279.85
  5. Step 5: Solve for x
    x = 8,279.85/85.25
  6. Step 6: Final answer
    x = 97.12

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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.