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Finding the Fourth Proportional to 57.30, 78.83 and 55.78

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Solution

The fourth proportional to 57.30, 78.83 and 55.78 is: 76.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.30 : 78.83 = 55.78 : x
  2. Step 2: Convert to fraction form
    57.30/78.83 = 55.78/x
  3. Step 3: Cross multiply
    57.30x = 78.83 × 55.78
  4. Step 4: Simplify right side
    57.30x = 4,396.74
  5. Step 5: Solve for x
    x = 4,396.74/57.30
  6. Step 6: Final answer
    x = 76.74

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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.