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Finding the Fourth Proportional to 638.43, 881.06 and 358.71

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Solution

The fourth proportional to 638.43, 881.06 and 358.71 is: 495.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.43 : 881.06 = 358.71 : x
  2. Step 2: Convert to fraction form
    638.43/881.06 = 358.71/x
  3. Step 3: Cross multiply
    638.43x = 881.06 × 358.71
  4. Step 4: Simplify right side
    638.43x = 316,043.24
  5. Step 5: Solve for x
    x = 316,043.24/638.43
  6. Step 6: Final answer
    x = 495.03

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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.