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Finding the Fourth Proportional to 644.79, 890.04 and 409.15

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Solution

The fourth proportional to 644.79, 890.04 and 409.15 is: 564.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.79 : 890.04 = 409.15 : x
  2. Step 2: Convert to fraction form
    644.79/890.04 = 409.15/x
  3. Step 3: Cross multiply
    644.79x = 890.04 × 409.15
  4. Step 4: Simplify right side
    644.79x = 364,159.87
  5. Step 5: Solve for x
    x = 364,159.87/644.79
  6. Step 6: Final answer
    x = 564.77

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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.