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Finding the Fourth Proportional to 645.17, 890.30 and 365.41

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Solution

The fourth proportional to 645.17, 890.30 and 365.41 is: 504.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.17 : 890.30 = 365.41 : x
  2. Step 2: Convert to fraction form
    645.17/890.30 = 365.41/x
  3. Step 3: Cross multiply
    645.17x = 890.30 × 365.41
  4. Step 4: Simplify right side
    645.17x = 325,325.91
  5. Step 5: Solve for x
    x = 325,325.91/645.17
  6. Step 6: Final answer
    x = 504.25

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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.