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Finding the Fourth Proportional to 645.85, 891.27 and 351.12

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Solution

The fourth proportional to 645.85, 891.27 and 351.12 is: 484.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.85 : 891.27 = 351.12 : x
  2. Step 2: Convert to fraction form
    645.85/891.27 = 351.12/x
  3. Step 3: Cross multiply
    645.85x = 891.27 × 351.12
  4. Step 4: Simplify right side
    645.85x = 312,942.72
  5. Step 5: Solve for x
    x = 312,942.72/645.85
  6. Step 6: Final answer
    x = 484.54

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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.