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Finding the Fourth Proportional to 645.03, 890.01 and 409.05

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Solution

The fourth proportional to 645.03, 890.01 and 409.05 is: 564.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.03 : 890.01 = 409.05 : x
  2. Step 2: Convert to fraction form
    645.03/890.01 = 409.05/x
  3. Step 3: Cross multiply
    645.03x = 890.01 × 409.05
  4. Step 4: Simplify right side
    645.03x = 364,058.59
  5. Step 5: Solve for x
    x = 364,058.59/645.03
  6. Step 6: Final answer
    x = 564.41

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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.