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Finding the Fourth Proportional to 89.38, 123.30 and 69.40

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Solution

The fourth proportional to 89.38, 123.30 and 69.40 is: 95.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.38 : 123.30 = 69.40 : x
  2. Step 2: Convert to fraction form
    89.38/123.30 = 69.40/x
  3. Step 3: Cross multiply
    89.38x = 123.30 × 69.40
  4. Step 4: Simplify right side
    89.38x = 8,557.02
  5. Step 5: Solve for x
    x = 8,557.02/89.38
  6. Step 6: Final answer
    x = 95.74

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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.