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Finding the Fourth Proportional to 644.29, 889.11 and 378.74

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Solution

The fourth proportional to 644.29, 889.11 and 378.74 is: 522.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.29 : 889.11 = 378.74 : x
  2. Step 2: Convert to fraction form
    644.29/889.11 = 378.74/x
  3. Step 3: Cross multiply
    644.29x = 889.11 × 378.74
  4. Step 4: Simplify right side
    644.29x = 336,743.74
  5. Step 5: Solve for x
    x = 336,743.74/644.29
  6. Step 6: Final answer
    x = 522.66

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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.