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Finding the Fourth Proportional to 620.20, 930.30 and 551.80

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Solution

The fourth proportional to 620.20, 930.30 and 551.80 is: 827.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.20 : 930.30 = 551.80 : x
  2. Step 2: Convert to fraction form
    620.20/930.30 = 551.80/x
  3. Step 3: Cross multiply
    620.20x = 930.30 × 551.80
  4. Step 4: Simplify right side
    620.20x = 513,339.54
  5. Step 5: Solve for x
    x = 513,339.54/620.20
  6. Step 6: Final answer
    x = 827.70

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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.