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Finding the Fourth Proportional to 540.15, 806.78 and 431.61

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Solution

The fourth proportional to 540.15, 806.78 and 431.61 is: 644.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.15 : 806.78 = 431.61 : x
  2. Step 2: Convert to fraction form
    540.15/806.78 = 431.61/x
  3. Step 3: Cross multiply
    540.15x = 806.78 × 431.61
  4. Step 4: Simplify right side
    540.15x = 348,212.16
  5. Step 5: Solve for x
    x = 348,212.16/540.15
  6. Step 6: Final answer
    x = 644.66

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.