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Finding the Fourth Proportional to 819.06, 1,129.93 and 487.30

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Solution

The fourth proportional to 819.06, 1,129.93 and 487.30 is: 672.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.06 : 1,129.93 = 487.30 : x
  2. Step 2: Convert to fraction form
    819.06/1,129.93 = 487.30/x
  3. Step 3: Cross multiply
    819.06x = 1,129.93 × 487.30
  4. Step 4: Simplify right side
    819.06x = 550,614.89
  5. Step 5: Solve for x
    x = 550,614.89/819.06
  6. Step 6: Final answer
    x = 672.25

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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.