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Finding the Fourth Proportional to 645.43, 890.50 and 406.18

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Solution

The fourth proportional to 645.43, 890.50 and 406.18 is: 560.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.43 : 890.50 = 406.18 : x
  2. Step 2: Convert to fraction form
    645.43/890.50 = 406.18/x
  3. Step 3: Cross multiply
    645.43x = 890.50 × 406.18
  4. Step 4: Simplify right side
    645.43x = 361,703.29
  5. Step 5: Solve for x
    x = 361,703.29/645.43
  6. Step 6: Final answer
    x = 560.41

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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.