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Finding the Fourth Proportional to 789.89, 1,089.72 and 579.71

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Solution

The fourth proportional to 789.89, 1,089.72 and 579.71 is: 799.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.89 : 1,089.72 = 579.71 : x
  2. Step 2: Convert to fraction form
    789.89/1,089.72 = 579.71/x
  3. Step 3: Cross multiply
    789.89x = 1,089.72 × 579.71
  4. Step 4: Simplify right side
    789.89x = 631,714.68
  5. Step 5: Solve for x
    x = 631,714.68/789.89
  6. Step 6: Final answer
    x = 799.75

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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.