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Finding the Fourth Proportional to 819.80, 1,131.24 and 470.42

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Solution

The fourth proportional to 819.80, 1,131.24 and 470.42 is: 649.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.80 : 1,131.24 = 470.42 : x
  2. Step 2: Convert to fraction form
    819.80/1,131.24 = 470.42/x
  3. Step 3: Cross multiply
    819.80x = 1,131.24 × 470.42
  4. Step 4: Simplify right side
    819.80x = 532,157.92
  5. Step 5: Solve for x
    x = 532,157.92/819.80
  6. Step 6: Final answer
    x = 649.13

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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.