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Finding the Fourth Proportional to 642.46, 963.45 and 209.50

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Solution

The fourth proportional to 642.46, 963.45 and 209.50 is: 314.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.46 : 963.45 = 209.50 : x
  2. Step 2: Convert to fraction form
    642.46/963.45 = 209.50/x
  3. Step 3: Cross multiply
    642.46x = 963.45 × 209.50
  4. Step 4: Simplify right side
    642.46x = 201,842.78
  5. Step 5: Solve for x
    x = 201,842.78/642.46
  6. Step 6: Final answer
    x = 314.17

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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.