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Finding the Fourth Proportional to 69.40, 103.98 and 57.28

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Solution

The fourth proportional to 69.40, 103.98 and 57.28 is: 85.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.40 : 103.98 = 57.28 : x
  2. Step 2: Convert to fraction form
    69.40/103.98 = 57.28/x
  3. Step 3: Cross multiply
    69.40x = 103.98 × 57.28
  4. Step 4: Simplify right side
    69.40x = 5,955.97
  5. Step 5: Solve for x
    x = 5,955.97/69.40
  6. Step 6: Final answer
    x = 85.82

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.