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Finding the Fourth Proportional to 645.42, 890.73 and 470.82

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Solution

The fourth proportional to 645.42, 890.73 and 470.82 is: 649.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.42 : 890.73 = 470.82 : x
  2. Step 2: Convert to fraction form
    645.42/890.73 = 470.82/x
  3. Step 3: Cross multiply
    645.42x = 890.73 × 470.82
  4. Step 4: Simplify right side
    645.42x = 419,373.50
  5. Step 5: Solve for x
    x = 419,373.50/645.42
  6. Step 6: Final answer
    x = 649.77

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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.