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Finding the Fourth Proportional to 645.23, 890.43 and 379.68

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Solution

The fourth proportional to 645.23, 890.43 and 379.68 is: 523.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.23 : 890.43 = 379.68 : x
  2. Step 2: Convert to fraction form
    645.23/890.43 = 379.68/x
  3. Step 3: Cross multiply
    645.23x = 890.43 × 379.68
  4. Step 4: Simplify right side
    645.23x = 338,079.74
  5. Step 5: Solve for x
    x = 338,079.74/645.23
  6. Step 6: Final answer
    x = 523.97

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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.