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Finding the Fourth Proportional to 638.40, 881.38 and 414.72

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Solution

The fourth proportional to 638.40, 881.38 and 414.72 is: 572.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.40 : 881.38 = 414.72 : x
  2. Step 2: Convert to fraction form
    638.40/881.38 = 414.72/x
  3. Step 3: Cross multiply
    638.40x = 881.38 × 414.72
  4. Step 4: Simplify right side
    638.40x = 365,525.91
  5. Step 5: Solve for x
    x = 365,525.91/638.40
  6. Step 6: Final answer
    x = 572.57

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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.