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Finding the Fourth Proportional to 642.91, 887.24 and 380.83

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Solution

The fourth proportional to 642.91, 887.24 and 380.83 is: 525.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.91 : 887.24 = 380.83 : x
  2. Step 2: Convert to fraction form
    642.91/887.24 = 380.83/x
  3. Step 3: Cross multiply
    642.91x = 887.24 × 380.83
  4. Step 4: Simplify right side
    642.91x = 337,887.61
  5. Step 5: Solve for x
    x = 337,887.61/642.91
  6. Step 6: Final answer
    x = 525.56

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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.