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Finding the Fourth Proportional to 645.58, 890.89 and 365.80

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Solution

The fourth proportional to 645.58, 890.89 and 365.80 is: 504.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.58 : 890.89 = 365.80 : x
  2. Step 2: Convert to fraction form
    645.58/890.89 = 365.80/x
  3. Step 3: Cross multiply
    645.58x = 890.89 × 365.80
  4. Step 4: Simplify right side
    645.58x = 325,887.56
  5. Step 5: Solve for x
    x = 325,887.56/645.58
  6. Step 6: Final answer
    x = 504.80

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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.