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Finding the Fourth Proportional to 644.60, 889.10 and 382.40

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Solution

The fourth proportional to 644.60, 889.10 and 382.40 is: 527.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.60 : 889.10 = 382.40 : x
  2. Step 2: Convert to fraction form
    644.60/889.10 = 382.40/x
  3. Step 3: Cross multiply
    644.60x = 889.10 × 382.40
  4. Step 4: Simplify right side
    644.60x = 339,991.84
  5. Step 5: Solve for x
    x = 339,991.84/644.60
  6. Step 6: Final answer
    x = 527.45

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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.