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Finding the Fourth Proportional to 638.49, 881.09 and 358.77

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Solution

The fourth proportional to 638.49, 881.09 and 358.77 is: 495.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.49 : 881.09 = 358.77 : x
  2. Step 2: Convert to fraction form
    638.49/881.09 = 358.77/x
  3. Step 3: Cross multiply
    638.49x = 881.09 × 358.77
  4. Step 4: Simplify right side
    638.49x = 316,108.66
  5. Step 5: Solve for x
    x = 316,108.66/638.49
  6. Step 6: Final answer
    x = 495.09

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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.