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Finding the Fourth Proportional to 645.03, 889.98 and 408.56

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Solution

The fourth proportional to 645.03, 889.98 and 408.56 is: 563.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.03 : 889.98 = 408.56 : x
  2. Step 2: Convert to fraction form
    645.03/889.98 = 408.56/x
  3. Step 3: Cross multiply
    645.03x = 889.98 × 408.56
  4. Step 4: Simplify right side
    645.03x = 363,604.25
  5. Step 5: Solve for x
    x = 363,604.25/645.03
  6. Step 6: Final answer
    x = 563.70

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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.