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Finding the Fourth Proportional to 638.07, 880.36 and 358.21

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Solution

The fourth proportional to 638.07, 880.36 and 358.21 is: 494.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.07 : 880.36 = 358.21 : x
  2. Step 2: Convert to fraction form
    638.07/880.36 = 358.21/x
  3. Step 3: Cross multiply
    638.07x = 880.36 × 358.21
  4. Step 4: Simplify right side
    638.07x = 315,353.76
  5. Step 5: Solve for x
    x = 315,353.76/638.07
  6. Step 6: Final answer
    x = 494.23

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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.