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Finding the Fourth Proportional to 721.88, 996.24 and 407.15

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Solution

The fourth proportional to 721.88, 996.24 and 407.15 is: 561.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.88 : 996.24 = 407.15 : x
  2. Step 2: Convert to fraction form
    721.88/996.24 = 407.15/x
  3. Step 3: Cross multiply
    721.88x = 996.24 × 407.15
  4. Step 4: Simplify right side
    721.88x = 405,619.12
  5. Step 5: Solve for x
    x = 405,619.12/721.88
  6. Step 6: Final answer
    x = 561.89

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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.