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Finding the Fourth Proportional to 213.30, 319.91 and 57.12

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Solution

The fourth proportional to 213.30, 319.91 and 57.12 is: 85.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    213.30 : 319.91 = 57.12 : x
  2. Step 2: Convert to fraction form
    213.30/319.91 = 57.12/x
  3. Step 3: Cross multiply
    213.30x = 319.91 × 57.12
  4. Step 4: Simplify right side
    213.30x = 18,273.92
  5. Step 5: Solve for x
    x = 18,273.92/213.30
  6. Step 6: Final answer
    x = 85.67

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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.