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Finding the Fourth Proportional to 638.19, 880.79 and 358.47

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Solution

The fourth proportional to 638.19, 880.79 and 358.47 is: 494.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.19 : 880.79 = 358.47 : x
  2. Step 2: Convert to fraction form
    638.19/880.79 = 358.47/x
  3. Step 3: Cross multiply
    638.19x = 880.79 × 358.47
  4. Step 4: Simplify right side
    638.19x = 315,735.00
  5. Step 5: Solve for x
    x = 315,735.00/638.19
  6. Step 6: Final answer
    x = 494.74

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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.