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Finding the Fourth Proportional to 645.25, 890.49 and 365.55

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Solution

The fourth proportional to 645.25, 890.49 and 365.55 is: 504.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.25 : 890.49 = 365.55 : x
  2. Step 2: Convert to fraction form
    645.25/890.49 = 365.55/x
  3. Step 3: Cross multiply
    645.25x = 890.49 × 365.55
  4. Step 4: Simplify right side
    645.25x = 325,522.07
  5. Step 5: Solve for x
    x = 325,522.07/645.25
  6. Step 6: Final answer
    x = 504.49

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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.