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Finding the Fourth Proportional to 77.10, 106.87 and 72.99

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Solution

The fourth proportional to 77.10, 106.87 and 72.99 is: 101.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.10 : 106.87 = 72.99 : x
  2. Step 2: Convert to fraction form
    77.10/106.87 = 72.99/x
  3. Step 3: Cross multiply
    77.10x = 106.87 × 72.99
  4. Step 4: Simplify right side
    77.10x = 7,800.44
  5. Step 5: Solve for x
    x = 7,800.44/77.10
  6. Step 6: Final answer
    x = 101.17

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.