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Finding the Fourth Proportional to 55.87, 77.05 and 39.47

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Solution

The fourth proportional to 55.87, 77.05 and 39.47 is: 54.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.87 : 77.05 = 39.47 : x
  2. Step 2: Convert to fraction form
    55.87/77.05 = 39.47/x
  3. Step 3: Cross multiply
    55.87x = 77.05 × 39.47
  4. Step 4: Simplify right side
    55.87x = 3,040.78
  5. Step 5: Solve for x
    x = 3,040.78/55.87
  6. Step 6: Final answer
    x = 54.43

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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.