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Finding the Fourth Proportional to 645.72, 890.62 and 397.04

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Solution

The fourth proportional to 645.72, 890.62 and 397.04 is: 547.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.72 : 890.62 = 397.04 : x
  2. Step 2: Convert to fraction form
    645.72/890.62 = 397.04/x
  3. Step 3: Cross multiply
    645.72x = 890.62 × 397.04
  4. Step 4: Simplify right side
    645.72x = 353,611.76
  5. Step 5: Solve for x
    x = 353,611.76/645.72
  6. Step 6: Final answer
    x = 547.62

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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.