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Finding the Fourth Proportional to 642.16, 963.39 and 209.35

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Solution

The fourth proportional to 642.16, 963.39 and 209.35 is: 314.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.16 : 963.39 = 209.35 : x
  2. Step 2: Convert to fraction form
    642.16/963.39 = 209.35/x
  3. Step 3: Cross multiply
    642.16x = 963.39 × 209.35
  4. Step 4: Simplify right side
    642.16x = 201,685.70
  5. Step 5: Solve for x
    x = 201,685.70/642.16
  6. Step 6: Final answer
    x = 314.07

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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.