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Finding the Fourth Proportional to 814.20, 1,214.31 and 727.80

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Solution

The fourth proportional to 814.20, 1,214.31 and 727.80 is: 1,085.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    814.20 : 1,214.31 = 727.80 : x
  2. Step 2: Convert to fraction form
    814.20/1,214.31 = 727.80/x
  3. Step 3: Cross multiply
    814.20x = 1,214.31 × 727.80
  4. Step 4: Simplify right side
    814.20x = 883,774.82
  5. Step 5: Solve for x
    x = 883,774.82/814.20
  6. Step 6: Final answer
    x = 1,085.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.