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Finding the Fourth Proportional to 807.52, 1,211.70 and 422.80

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Solution

The fourth proportional to 807.52, 1,211.70 and 422.80 is: 634.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.52 : 1,211.70 = 422.80 : x
  2. Step 2: Convert to fraction form
    807.52/1,211.70 = 422.80/x
  3. Step 3: Cross multiply
    807.52x = 1,211.70 × 422.80
  4. Step 4: Simplify right side
    807.52x = 512,306.76
  5. Step 5: Solve for x
    x = 512,306.76/807.52
  6. Step 6: Final answer
    x = 634.42

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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.