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Finding the Fourth Proportional to 642.56, 963.83 and 155.61

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Solution

The fourth proportional to 642.56, 963.83 and 155.61 is: 233.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.56 : 963.83 = 155.61 : x
  2. Step 2: Convert to fraction form
    642.56/963.83 = 155.61/x
  3. Step 3: Cross multiply
    642.56x = 963.83 × 155.61
  4. Step 4: Simplify right side
    642.56x = 149,977.16
  5. Step 5: Solve for x
    x = 149,977.16/642.56
  6. Step 6: Final answer
    x = 233.41

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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.