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Finding the Fourth Proportional to 89.22, 123.02 and 78.28

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Solution

The fourth proportional to 89.22, 123.02 and 78.28 is: 107.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.22 : 123.02 = 78.28 : x
  2. Step 2: Convert to fraction form
    89.22/123.02 = 78.28/x
  3. Step 3: Cross multiply
    89.22x = 123.02 × 78.28
  4. Step 4: Simplify right side
    89.22x = 9,630.01
  5. Step 5: Solve for x
    x = 9,630.01/89.22
  6. Step 6: Final answer
    x = 107.94

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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.