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Finding the Fourth Proportional to 89.70, 123.28 and 89.29

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Solution

The fourth proportional to 89.70, 123.28 and 89.29 is: 122.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.70 : 123.28 = 89.29 : x
  2. Step 2: Convert to fraction form
    89.70/123.28 = 89.29/x
  3. Step 3: Cross multiply
    89.70x = 123.28 × 89.29
  4. Step 4: Simplify right side
    89.70x = 11,007.67
  5. Step 5: Solve for x
    x = 11,007.67/89.70
  6. Step 6: Final answer
    x = 122.72

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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.