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Finding the Fourth Proportional to 721.60, 995.74 and 406.88

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Solution

The fourth proportional to 721.60, 995.74 and 406.88 is: 561.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.60 : 995.74 = 406.88 : x
  2. Step 2: Convert to fraction form
    721.60/995.74 = 406.88/x
  3. Step 3: Cross multiply
    721.60x = 995.74 × 406.88
  4. Step 4: Simplify right side
    721.60x = 405,146.69
  5. Step 5: Solve for x
    x = 405,146.69/721.60
  6. Step 6: Final answer
    x = 561.46

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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.