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Finding the Fourth Proportional to 71.87, 107.90 and 45.77

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Solution

The fourth proportional to 71.87, 107.90 and 45.77 is: 68.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.87 : 107.90 = 45.77 : x
  2. Step 2: Convert to fraction form
    71.87/107.90 = 45.77/x
  3. Step 3: Cross multiply
    71.87x = 107.90 × 45.77
  4. Step 4: Simplify right side
    71.87x = 4,937.81
  5. Step 5: Solve for x
    x = 4,937.81/71.87
  6. Step 6: Final answer
    x = 68.71

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.