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Finding the Fourth Proportional to 642.09, 963.28 and 209.24

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Solution

The fourth proportional to 642.09, 963.28 and 209.24 is: 313.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.09 : 963.28 = 209.24 : x
  2. Step 2: Convert to fraction form
    642.09/963.28 = 209.24/x
  3. Step 3: Cross multiply
    642.09x = 963.28 × 209.24
  4. Step 4: Simplify right side
    642.09x = 201,556.71
  5. Step 5: Solve for x
    x = 201,556.71/642.09
  6. Step 6: Final answer
    x = 313.91

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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.