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Finding the Fourth Proportional to 814.10, 1,221.15 and 808.70

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Solution

The fourth proportional to 814.10, 1,221.15 and 808.70 is: 1,213.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    814.10 : 1,221.15 = 808.70 : x
  2. Step 2: Convert to fraction form
    814.10/1,221.15 = 808.70/x
  3. Step 3: Cross multiply
    814.10x = 1,221.15 × 808.70
  4. Step 4: Simplify right side
    814.10x = 987,544.01
  5. Step 5: Solve for x
    x = 987,544.01/814.10
  6. Step 6: Final answer
    x = 1,213.05

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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.