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Finding the Fourth Proportional to 645.13, 890.88 and 449.18

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Solution

The fourth proportional to 645.13, 890.88 and 449.18 is: 620.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.13 : 890.88 = 449.18 : x
  2. Step 2: Convert to fraction form
    645.13/890.88 = 449.18/x
  3. Step 3: Cross multiply
    645.13x = 890.88 × 449.18
  4. Step 4: Simplify right side
    645.13x = 400,161.02
  5. Step 5: Solve for x
    x = 400,161.02/645.13
  6. Step 6: Final answer
    x = 620.28

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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.