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Finding the Fourth Proportional to 881.72, 1,321.63 and 387.69

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Solution

The fourth proportional to 881.72, 1,321.63 and 387.69 is: 581.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    881.72 : 1,321.63 = 387.69 : x
  2. Step 2: Convert to fraction form
    881.72/1,321.63 = 387.69/x
  3. Step 3: Cross multiply
    881.72x = 1,321.63 × 387.69
  4. Step 4: Simplify right side
    881.72x = 512,374.19
  5. Step 5: Solve for x
    x = 512,374.19/881.72
  6. Step 6: Final answer
    x = 581.11

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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.