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Finding the Fourth Proportional to 820.50, 1,230.54 and 511.22

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Solution

The fourth proportional to 820.50, 1,230.54 and 511.22 is: 766.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.50 : 1,230.54 = 511.22 : x
  2. Step 2: Convert to fraction form
    820.50/1,230.54 = 511.22/x
  3. Step 3: Cross multiply
    820.50x = 1,230.54 × 511.22
  4. Step 4: Simplify right side
    820.50x = 629,076.66
  5. Step 5: Solve for x
    x = 629,076.66/820.50
  6. Step 6: Final answer
    x = 766.70

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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.