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Finding the Fourth Proportional to 658.12, 986.85 and 219.21

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Solution

The fourth proportional to 658.12, 986.85 and 219.21 is: 328.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.12 : 986.85 = 219.21 : x
  2. Step 2: Convert to fraction form
    658.12/986.85 = 219.21/x
  3. Step 3: Cross multiply
    658.12x = 986.85 × 219.21
  4. Step 4: Simplify right side
    658.12x = 216,328.76
  5. Step 5: Solve for x
    x = 216,328.76/658.12
  6. Step 6: Final answer
    x = 328.71

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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.