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Finding the Fourth Proportional to 104.80, 157.04 and 81.87

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Solution

The fourth proportional to 104.80, 157.04 and 81.87 is: 122.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    104.80 : 157.04 = 81.87 : x
  2. Step 2: Convert to fraction form
    104.80/157.04 = 81.87/x
  3. Step 3: Cross multiply
    104.80x = 157.04 × 81.87
  4. Step 4: Simplify right side
    104.80x = 12,856.08
  5. Step 5: Solve for x
    x = 12,856.08/104.80
  6. Step 6: Final answer
    x = 122.68

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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.