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Finding the Fourth Proportional to 645.46, 890.35 and 459.21

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Solution

The fourth proportional to 645.46, 890.35 and 459.21 is: 633.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.46 : 890.35 = 459.21 : x
  2. Step 2: Convert to fraction form
    645.46/890.35 = 459.21/x
  3. Step 3: Cross multiply
    645.46x = 890.35 × 459.21
  4. Step 4: Simplify right side
    645.46x = 408,853.17
  5. Step 5: Solve for x
    x = 408,853.17/645.46
  6. Step 6: Final answer
    x = 633.43

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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.