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Finding the Fourth Proportional to 638.47, 881.06 and 358.70

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Solution

The fourth proportional to 638.47, 881.06 and 358.70 is: 494.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.47 : 881.06 = 358.70 : x
  2. Step 2: Convert to fraction form
    638.47/881.06 = 358.70/x
  3. Step 3: Cross multiply
    638.47x = 881.06 × 358.70
  4. Step 4: Simplify right side
    638.47x = 316,036.22
  5. Step 5: Solve for x
    x = 316,036.22/638.47
  6. Step 6: Final answer
    x = 494.99

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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.