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Finding the Fourth Proportional to 769.71, 1,062.23 and 420.39

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Solution

The fourth proportional to 769.71, 1,062.23 and 420.39 is: 580.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    769.71 : 1,062.23 = 420.39 : x
  2. Step 2: Convert to fraction form
    769.71/1,062.23 = 420.39/x
  3. Step 3: Cross multiply
    769.71x = 1,062.23 × 420.39
  4. Step 4: Simplify right side
    769.71x = 446,550.87
  5. Step 5: Solve for x
    x = 446,550.87/769.71
  6. Step 6: Final answer
    x = 580.15

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.