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Finding the Fourth Proportional to 808.47, 1,218.92 and 648.09

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Solution

The fourth proportional to 808.47, 1,218.92 and 648.09 is: 977.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.47 : 1,218.92 = 648.09 : x
  2. Step 2: Convert to fraction form
    808.47/1,218.92 = 648.09/x
  3. Step 3: Cross multiply
    808.47x = 1,218.92 × 648.09
  4. Step 4: Simplify right side
    808.47x = 789,966.62
  5. Step 5: Solve for x
    x = 789,966.62/808.47
  6. Step 6: Final answer
    x = 977.11

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.