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Finding the Fourth Proportional to 77.30, 106.61 and 57.69

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Solution

The fourth proportional to 77.30, 106.61 and 57.69 is: 79.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.30 : 106.61 = 57.69 : x
  2. Step 2: Convert to fraction form
    77.30/106.61 = 57.69/x
  3. Step 3: Cross multiply
    77.30x = 106.61 × 57.69
  4. Step 4: Simplify right side
    77.30x = 6,150.87
  5. Step 5: Solve for x
    x = 6,150.87/77.30
  6. Step 6: Final answer
    x = 79.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.