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Finding the Fourth Proportional to 206.03, 309.05 and 57.78

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Solution

The fourth proportional to 206.03, 309.05 and 57.78 is: 86.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.03 : 309.05 = 57.78 : x
  2. Step 2: Convert to fraction form
    206.03/309.05 = 57.78/x
  3. Step 3: Cross multiply
    206.03x = 309.05 × 57.78
  4. Step 4: Simplify right side
    206.03x = 17,856.91
  5. Step 5: Solve for x
    x = 17,856.91/206.03
  6. Step 6: Final answer
    x = 86.67

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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.