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Finding the Fourth Proportional to 642.77, 963.93 and 209.82

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Solution

The fourth proportional to 642.77, 963.93 and 209.82 is: 314.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.77 : 963.93 = 209.82 : x
  2. Step 2: Convert to fraction form
    642.77/963.93 = 209.82/x
  3. Step 3: Cross multiply
    642.77x = 963.93 × 209.82
  4. Step 4: Simplify right side
    642.77x = 202,251.79
  5. Step 5: Solve for x
    x = 202,251.79/642.77
  6. Step 6: Final answer
    x = 314.66

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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.