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Finding the Fourth Proportional to 644.55, 890.60 and 479.31

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Solution

The fourth proportional to 644.55, 890.60 and 479.31 is: 662.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.55 : 890.60 = 479.31 : x
  2. Step 2: Convert to fraction form
    644.55/890.60 = 479.31/x
  3. Step 3: Cross multiply
    644.55x = 890.60 × 479.31
  4. Step 4: Simplify right side
    644.55x = 426,871.09
  5. Step 5: Solve for x
    x = 426,871.09/644.55
  6. Step 6: Final answer
    x = 662.28

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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.