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Finding the Fourth Proportional to 644.70, 889.74 and 382.80

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Solution

The fourth proportional to 644.70, 889.74 and 382.80 is: 528.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.70 : 889.74 = 382.80 : x
  2. Step 2: Convert to fraction form
    644.70/889.74 = 382.80/x
  3. Step 3: Cross multiply
    644.70x = 889.74 × 382.80
  4. Step 4: Simplify right side
    644.70x = 340,592.47
  5. Step 5: Solve for x
    x = 340,592.47/644.70
  6. Step 6: Final answer
    x = 528.30

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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.