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Finding the Fourth Proportional to 639.49, 882.49 and 355.91

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Solution

The fourth proportional to 639.49, 882.49 and 355.91 is: 491.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.49 : 882.49 = 355.91 : x
  2. Step 2: Convert to fraction form
    639.49/882.49 = 355.91/x
  3. Step 3: Cross multiply
    639.49x = 882.49 × 355.91
  4. Step 4: Simplify right side
    639.49x = 314,082.38
  5. Step 5: Solve for x
    x = 314,082.38/639.49
  6. Step 6: Final answer
    x = 491.14

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.