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Finding the Fourth Proportional to 642.51, 963.89 and 272.55

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Solution

The fourth proportional to 642.51, 963.89 and 272.55 is: 408.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.51 : 963.89 = 272.55 : x
  2. Step 2: Convert to fraction form
    642.51/963.89 = 272.55/x
  3. Step 3: Cross multiply
    642.51x = 963.89 × 272.55
  4. Step 4: Simplify right side
    642.51x = 262,706.86
  5. Step 5: Solve for x
    x = 262,706.86/642.51
  6. Step 6: Final answer
    x = 408.88

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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.