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Finding the Fourth Proportional to 812.00, 1,218.47 and 805.39

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Solution

The fourth proportional to 812.00, 1,218.47 and 805.39 is: 1,208.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.00 : 1,218.47 = 805.39 : x
  2. Step 2: Convert to fraction form
    812.00/1,218.47 = 805.39/x
  3. Step 3: Cross multiply
    812.00x = 1,218.47 × 805.39
  4. Step 4: Simplify right side
    812.00x = 981,346.03
  5. Step 5: Solve for x
    x = 981,346.03/812.00
  6. Step 6: Final answer
    x = 1,208.55

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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.