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Finding the Fourth Proportional to 819.20, 1,129.29 and 569.82

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Solution

The fourth proportional to 819.20, 1,129.29 and 569.82 is: 785.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.20 : 1,129.29 = 569.82 : x
  2. Step 2: Convert to fraction form
    819.20/1,129.29 = 569.82/x
  3. Step 3: Cross multiply
    819.20x = 1,129.29 × 569.82
  4. Step 4: Simplify right side
    819.20x = 643,492.03
  5. Step 5: Solve for x
    x = 643,492.03/819.20
  6. Step 6: Final answer
    x = 785.52

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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.