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Finding the Fourth Proportional to 77.58, 115.81 and 55.74

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Solution

The fourth proportional to 77.58, 115.81 and 55.74 is: 83.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.58 : 115.81 = 55.74 : x
  2. Step 2: Convert to fraction form
    77.58/115.81 = 55.74/x
  3. Step 3: Cross multiply
    77.58x = 115.81 × 55.74
  4. Step 4: Simplify right side
    77.58x = 6,455.25
  5. Step 5: Solve for x
    x = 6,455.25/77.58
  6. Step 6: Final answer
    x = 83.21

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.