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Finding the Fourth Proportional to 63.45, 86.97 and 61.90

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Solution

The fourth proportional to 63.45, 86.97 and 61.90 is: 84.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.45 : 86.97 = 61.90 : x
  2. Step 2: Convert to fraction form
    63.45/86.97 = 61.90/x
  3. Step 3: Cross multiply
    63.45x = 86.97 × 61.90
  4. Step 4: Simplify right side
    63.45x = 5,383.46
  5. Step 5: Solve for x
    x = 5,383.46/63.45
  6. Step 6: Final answer
    x = 84.85

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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.