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Finding the Fourth Proportional to 57.09, 85.66 and 39.98

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Solution

The fourth proportional to 57.09, 85.66 and 39.98 is: 59.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.09 : 85.66 = 39.98 : x
  2. Step 2: Convert to fraction form
    57.09/85.66 = 39.98/x
  3. Step 3: Cross multiply
    57.09x = 85.66 × 39.98
  4. Step 4: Simplify right side
    57.09x = 3,424.69
  5. Step 5: Solve for x
    x = 3,424.69/57.09
  6. Step 6: Final answer
    x = 59.99

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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.