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Finding the Fourth Proportional to 722.68, 997.21 and 407.90

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Solution

The fourth proportional to 722.68, 997.21 and 407.90 is: 562.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    722.68 : 997.21 = 407.90 : x
  2. Step 2: Convert to fraction form
    722.68/997.21 = 407.90/x
  3. Step 3: Cross multiply
    722.68x = 997.21 × 407.90
  4. Step 4: Simplify right side
    722.68x = 406,761.96
  5. Step 5: Solve for x
    x = 406,761.96/722.68
  6. Step 6: Final answer
    x = 562.85

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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.