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Finding the Fourth Proportional to 638.14, 879.84 and 413.70

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Solution

The fourth proportional to 638.14, 879.84 and 413.70 is: 570.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.14 : 879.84 = 413.70 : x
  2. Step 2: Convert to fraction form
    638.14/879.84 = 413.70/x
  3. Step 3: Cross multiply
    638.14x = 879.84 × 413.70
  4. Step 4: Simplify right side
    638.14x = 363,989.81
  5. Step 5: Solve for x
    x = 363,989.81/638.14
  6. Step 6: Final answer
    x = 570.39

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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.