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Finding the Fourth Proportional to 814.38, 1,219.68 and 678.30

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Solution

The fourth proportional to 814.38, 1,219.68 and 678.30 is: 1,015.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    814.38 : 1,219.68 = 678.30 : x
  2. Step 2: Convert to fraction form
    814.38/1,219.68 = 678.30/x
  3. Step 3: Cross multiply
    814.38x = 1,219.68 × 678.30
  4. Step 4: Simplify right side
    814.38x = 827,308.94
  5. Step 5: Solve for x
    x = 827,308.94/814.38
  6. Step 6: Final answer
    x = 1,015.88

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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.