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Finding the Fourth Proportional to 819.50, 1,130.91 and 470.21

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Solution

The fourth proportional to 819.50, 1,130.91 and 470.21 is: 648.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.50 : 1,130.91 = 470.21 : x
  2. Step 2: Convert to fraction form
    819.50/1,130.91 = 470.21/x
  3. Step 3: Cross multiply
    819.50x = 1,130.91 × 470.21
  4. Step 4: Simplify right side
    819.50x = 531,765.19
  5. Step 5: Solve for x
    x = 531,765.19/819.50
  6. Step 6: Final answer
    x = 648.89

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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.