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Finding the Fourth Proportional to 620.86, 931.44 and 438.61

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Solution

The fourth proportional to 620.86, 931.44 and 438.61 is: 658.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.86 : 931.44 = 438.61 : x
  2. Step 2: Convert to fraction form
    620.86/931.44 = 438.61/x
  3. Step 3: Cross multiply
    620.86x = 931.44 × 438.61
  4. Step 4: Simplify right side
    620.86x = 408,538.90
  5. Step 5: Solve for x
    x = 408,538.90/620.86
  6. Step 6: Final answer
    x = 658.02

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.