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Finding the Fourth Proportional to 77.07, 115.43 and 56.91

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Solution

The fourth proportional to 77.07, 115.43 and 56.91 is: 85.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.07 : 115.43 = 56.91 : x
  2. Step 2: Convert to fraction form
    77.07/115.43 = 56.91/x
  3. Step 3: Cross multiply
    77.07x = 115.43 × 56.91
  4. Step 4: Simplify right side
    77.07x = 6,568.84
  5. Step 5: Solve for x
    x = 6,568.84/77.07
  6. Step 6: Final answer
    x = 85.23

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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.