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Finding the Fourth Proportional to 638.30, 880.80 and 358.57

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Solution

The fourth proportional to 638.30, 880.80 and 358.57 is: 494.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.30 : 880.80 = 358.57 : x
  2. Step 2: Convert to fraction form
    638.30/880.80 = 358.57/x
  3. Step 3: Cross multiply
    638.30x = 880.80 × 358.57
  4. Step 4: Simplify right side
    638.30x = 315,826.66
  5. Step 5: Solve for x
    x = 315,826.66/638.30
  6. Step 6: Final answer
    x = 494.80

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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.