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Finding the Fourth Proportional to 56.87, 78.89 and 53.90

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Solution

The fourth proportional to 56.87, 78.89 and 53.90 is: 74.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    56.87 : 78.89 = 53.90 : x
  2. Step 2: Convert to fraction form
    56.87/78.89 = 53.90/x
  3. Step 3: Cross multiply
    56.87x = 78.89 × 53.90
  4. Step 4: Simplify right side
    56.87x = 4,251.91
  5. Step 5: Solve for x
    x = 4,251.91/56.87
  6. Step 6: Final answer
    x = 74.77

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.