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Finding the Fourth Proportional to 819.80, 1,131.36 and 470.56

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Solution

The fourth proportional to 819.80, 1,131.36 and 470.56 is: 649.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.80 : 1,131.36 = 470.56 : x
  2. Step 2: Convert to fraction form
    819.80/1,131.36 = 470.56/x
  3. Step 3: Cross multiply
    819.80x = 1,131.36 × 470.56
  4. Step 4: Simplify right side
    819.80x = 532,372.76
  5. Step 5: Solve for x
    x = 532,372.76/819.80
  6. Step 6: Final answer
    x = 649.39

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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.