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Finding the Fourth Proportional to 871.85, 1,203.11 and 478.85

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Solution

The fourth proportional to 871.85, 1,203.11 and 478.85 is: 660.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.85 : 1,203.11 = 478.85 : x
  2. Step 2: Convert to fraction form
    871.85/1,203.11 = 478.85/x
  3. Step 3: Cross multiply
    871.85x = 1,203.11 × 478.85
  4. Step 4: Simplify right side
    871.85x = 576,100.81
  5. Step 5: Solve for x
    x = 576,100.81/871.85
  6. Step 6: Final answer
    x = 660.78

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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.