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Finding the Fourth Proportional to 819.78, 1,220.53 and 808.29

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Solution

The fourth proportional to 819.78, 1,220.53 and 808.29 is: 1,203.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.78 : 1,220.53 = 808.29 : x
  2. Step 2: Convert to fraction form
    819.78/1,220.53 = 808.29/x
  3. Step 3: Cross multiply
    819.78x = 1,220.53 × 808.29
  4. Step 4: Simplify right side
    819.78x = 986,540.17
  5. Step 5: Solve for x
    x = 986,540.17/819.78
  6. Step 6: Final answer
    x = 1,203.42

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.