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Finding the Fourth Proportional to 89.31, 123.11 and 70.85

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Solution

The fourth proportional to 89.31, 123.11 and 70.85 is: 97.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.31 : 123.11 = 70.85 : x
  2. Step 2: Convert to fraction form
    89.31/123.11 = 70.85/x
  3. Step 3: Cross multiply
    89.31x = 123.11 × 70.85
  4. Step 4: Simplify right side
    89.31x = 8,722.34
  5. Step 5: Solve for x
    x = 8,722.34/89.31
  6. Step 6: Final answer
    x = 97.66

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.