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Finding the Fourth Proportional to 644.42, 889.33 and 408.28

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Solution

The fourth proportional to 644.42, 889.33 and 408.28 is: 563.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.42 : 889.33 = 408.28 : x
  2. Step 2: Convert to fraction form
    644.42/889.33 = 408.28/x
  3. Step 3: Cross multiply
    644.42x = 889.33 × 408.28
  4. Step 4: Simplify right side
    644.42x = 363,089.16
  5. Step 5: Solve for x
    x = 363,089.16/644.42
  6. Step 6: Final answer
    x = 563.44

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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.