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Finding the Fourth Proportional to 768.39, 1,151.88 and 281.31

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Solution

The fourth proportional to 768.39, 1,151.88 and 281.31 is: 421.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    768.39 : 1,151.88 = 281.31 : x
  2. Step 2: Convert to fraction form
    768.39/1,151.88 = 281.31/x
  3. Step 3: Cross multiply
    768.39x = 1,151.88 × 281.31
  4. Step 4: Simplify right side
    768.39x = 324,035.36
  5. Step 5: Solve for x
    x = 324,035.36/768.39
  6. Step 6: Final answer
    x = 421.71

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.