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Finding the Fourth Proportional to 645.20, 890.38 and 350.47

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Solution

The fourth proportional to 645.20, 890.38 and 350.47 is: 483.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.20 : 890.38 = 350.47 : x
  2. Step 2: Convert to fraction form
    645.20/890.38 = 350.47/x
  3. Step 3: Cross multiply
    645.20x = 890.38 × 350.47
  4. Step 4: Simplify right side
    645.20x = 312,045.27
  5. Step 5: Solve for x
    x = 312,045.27/645.20
  6. Step 6: Final answer
    x = 483.64

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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.