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Finding the Fourth Proportional to 77.39, 115.97 and 70.87

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Solution

The fourth proportional to 77.39, 115.97 and 70.87 is: 106.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.39 : 115.97 = 70.87 : x
  2. Step 2: Convert to fraction form
    77.39/115.97 = 70.87/x
  3. Step 3: Cross multiply
    77.39x = 115.97 × 70.87
  4. Step 4: Simplify right side
    77.39x = 8,218.21
  5. Step 5: Solve for x
    x = 8,218.21/77.39
  6. Step 6: Final answer
    x = 106.19

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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.