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Finding the Fourth Proportional to 642.03, 963.15 and 209.10

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Solution

The fourth proportional to 642.03, 963.15 and 209.10 is: 313.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.03 : 963.15 = 209.10 : x
  2. Step 2: Convert to fraction form
    642.03/963.15 = 209.10/x
  3. Step 3: Cross multiply
    642.03x = 963.15 × 209.10
  4. Step 4: Simplify right side
    642.03x = 201,394.67
  5. Step 5: Solve for x
    x = 201,394.67/642.03
  6. Step 6: Final answer
    x = 313.68

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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.