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Finding the Fourth Proportional to 721.74, 995.90 and 406.99

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Solution

The fourth proportional to 721.74, 995.90 and 406.99 is: 561.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.74 : 995.90 = 406.99 : x
  2. Step 2: Convert to fraction form
    721.74/995.90 = 406.99/x
  3. Step 3: Cross multiply
    721.74x = 995.90 × 406.99
  4. Step 4: Simplify right side
    721.74x = 405,320.55
  5. Step 5: Solve for x
    x = 405,320.55/721.74
  6. Step 6: Final answer
    x = 561.59

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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.