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Finding the Fourth Proportional to 642.87, 963.75 and 272.66

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Solution

The fourth proportional to 642.87, 963.75 and 272.66 is: 408.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.87 : 963.75 = 272.66 : x
  2. Step 2: Convert to fraction form
    642.87/963.75 = 272.66/x
  3. Step 3: Cross multiply
    642.87x = 963.75 × 272.66
  4. Step 4: Simplify right side
    642.87x = 262,776.08
  5. Step 5: Solve for x
    x = 262,776.08/642.87
  6. Step 6: Final answer
    x = 408.75

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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.