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Finding the Fourth Proportional to 814.95, 1,220.09 and 620.70

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Solution

The fourth proportional to 814.95, 1,220.09 and 620.70 is: 929.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    814.95 : 1,220.09 = 620.70 : x
  2. Step 2: Convert to fraction form
    814.95/1,220.09 = 620.70/x
  3. Step 3: Cross multiply
    814.95x = 1,220.09 × 620.70
  4. Step 4: Simplify right side
    814.95x = 757,306.76
  5. Step 5: Solve for x
    x = 757,306.76/814.95
  6. Step 6: Final answer
    x = 929.27

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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.