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Finding the Fourth Proportional to 645.18, 890.41 and 365.49

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Solution

The fourth proportional to 645.18, 890.41 and 365.49 is: 504.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.18 : 890.41 = 365.49 : x
  2. Step 2: Convert to fraction form
    645.18/890.41 = 365.49/x
  3. Step 3: Cross multiply
    645.18x = 890.41 × 365.49
  4. Step 4: Simplify right side
    645.18x = 325,431.68
  5. Step 5: Solve for x
    x = 325,431.68/645.18
  6. Step 6: Final answer
    x = 504.40

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Double scale
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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.