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Finding the Fourth Proportional to 638.90, 881.66 and 359.15

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Solution

The fourth proportional to 638.90, 881.66 and 359.15 is: 495.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.90 : 881.66 = 359.15 : x
  2. Step 2: Convert to fraction form
    638.90/881.66 = 359.15/x
  3. Step 3: Cross multiply
    638.90x = 881.66 × 359.15
  4. Step 4: Simplify right side
    638.90x = 316,641.98
  5. Step 5: Solve for x
    x = 316,641.98/638.90
  6. Step 6: Final answer
    x = 495.61

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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.