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Finding the Fourth Proportional to 819.09, 1,130.40 and 469.79

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Solution

The fourth proportional to 819.09, 1,130.40 and 469.79 is: 648.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.09 : 1,130.40 = 469.79 : x
  2. Step 2: Convert to fraction form
    819.09/1,130.40 = 469.79/x
  3. Step 3: Cross multiply
    819.09x = 1,130.40 × 469.79
  4. Step 4: Simplify right side
    819.09x = 531,044.96
  5. Step 5: Solve for x
    x = 531,044.96/819.09
  6. Step 6: Final answer
    x = 648.34

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.