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Finding the Fourth Proportional to 789.72, 1,089.82 and 435.65

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Solution

The fourth proportional to 789.72, 1,089.82 and 435.65 is: 601.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.72 : 1,089.82 = 435.65 : x
  2. Step 2: Convert to fraction form
    789.72/1,089.82 = 435.65/x
  3. Step 3: Cross multiply
    789.72x = 1,089.82 × 435.65
  4. Step 4: Simplify right side
    789.72x = 474,778.86
  5. Step 5: Solve for x
    x = 474,778.86/789.72
  6. Step 6: Final answer
    x = 601.20

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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.