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Finding the Fourth Proportional to 645.07, 890.53 and 409.26

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Solution

The fourth proportional to 645.07, 890.53 and 409.26 is: 564.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.07 : 890.53 = 409.26 : x
  2. Step 2: Convert to fraction form
    645.07/890.53 = 409.26/x
  3. Step 3: Cross multiply
    645.07x = 890.53 × 409.26
  4. Step 4: Simplify right side
    645.07x = 364,458.12
  5. Step 5: Solve for x
    x = 364,458.12/645.07
  6. Step 6: Final answer
    x = 564.99

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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.