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Finding the Fourth Proportional to 638.30, 880.84 and 358.55

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Solution

The fourth proportional to 638.30, 880.84 and 358.55 is: 494.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.30 : 880.84 = 358.55 : x
  2. Step 2: Convert to fraction form
    638.30/880.84 = 358.55/x
  3. Step 3: Cross multiply
    638.30x = 880.84 × 358.55
  4. Step 4: Simplify right side
    638.30x = 315,825.18
  5. Step 5: Solve for x
    x = 315,825.18/638.30
  6. Step 6: Final answer
    x = 494.79

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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.