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Finding the Fourth Proportional to 721.32, 995.40 and 406.60

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Solution

The fourth proportional to 721.32, 995.40 and 406.60 is: 561.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.32 : 995.40 = 406.60 : x
  2. Step 2: Convert to fraction form
    721.32/995.40 = 406.60/x
  3. Step 3: Cross multiply
    721.32x = 995.40 × 406.60
  4. Step 4: Simplify right side
    721.32x = 404,729.64
  5. Step 5: Solve for x
    x = 404,729.64/721.32
  6. Step 6: Final answer
    x = 561.10

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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.