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Finding the Fourth Proportional to 57.10, 78.99 and 55.90

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Solution

The fourth proportional to 57.10, 78.99 and 55.90 is: 77.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.10 : 78.99 = 55.90 : x
  2. Step 2: Convert to fraction form
    57.10/78.99 = 55.90/x
  3. Step 3: Cross multiply
    57.10x = 78.99 × 55.90
  4. Step 4: Simplify right side
    57.10x = 4,415.54
  5. Step 5: Solve for x
    x = 4,415.54/57.10
  6. Step 6: Final answer
    x = 77.33

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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.