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Finding the Fourth Proportional to 645.14, 890.52 and 470.72

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Solution

The fourth proportional to 645.14, 890.52 and 470.72 is: 649.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.14 : 890.52 = 470.72 : x
  2. Step 2: Convert to fraction form
    645.14/890.52 = 470.72/x
  3. Step 3: Cross multiply
    645.14x = 890.52 × 470.72
  4. Step 4: Simplify right side
    645.14x = 419,185.57
  5. Step 5: Solve for x
    x = 419,185.57/645.14
  6. Step 6: Final answer
    x = 649.76

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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.