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Finding the Fourth Proportional to 645.73, 891.27 and 397.23

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Solution

The fourth proportional to 645.73, 891.27 and 397.23 is: 548.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.73 : 891.27 = 397.23 : x
  2. Step 2: Convert to fraction form
    645.73/891.27 = 397.23/x
  3. Step 3: Cross multiply
    645.73x = 891.27 × 397.23
  4. Step 4: Simplify right side
    645.73x = 354,039.18
  5. Step 5: Solve for x
    x = 354,039.18/645.73
  6. Step 6: Final answer
    x = 548.28

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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.