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Finding the Fourth Proportional to 619.70, 928.20 and 538.70

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Solution

The fourth proportional to 619.70, 928.20 and 538.70 is: 806.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.70 : 928.20 = 538.70 : x
  2. Step 2: Convert to fraction form
    619.70/928.20 = 538.70/x
  3. Step 3: Cross multiply
    619.70x = 928.20 × 538.70
  4. Step 4: Simplify right side
    619.70x = 500,021.34
  5. Step 5: Solve for x
    x = 500,021.34/619.70
  6. Step 6: Final answer
    x = 806.88

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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.