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Finding the Fourth Proportional to 819.80, 1,131.42 and 470.50

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Solution

The fourth proportional to 819.80, 1,131.42 and 470.50 is: 649.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.80 : 1,131.42 = 470.50 : x
  2. Step 2: Convert to fraction form
    819.80/1,131.42 = 470.50/x
  3. Step 3: Cross multiply
    819.80x = 1,131.42 × 470.50
  4. Step 4: Simplify right side
    819.80x = 532,333.11
  5. Step 5: Solve for x
    x = 532,333.11/819.80
  6. Step 6: Final answer
    x = 649.35

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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.