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Finding the Fourth Proportional to 721.30, 995.19 and 406.45

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Solution

The fourth proportional to 721.30, 995.19 and 406.45 is: 560.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.30 : 995.19 = 406.45 : x
  2. Step 2: Convert to fraction form
    721.30/995.19 = 406.45/x
  3. Step 3: Cross multiply
    721.30x = 995.19 × 406.45
  4. Step 4: Simplify right side
    721.30x = 404,492.94
  5. Step 5: Solve for x
    x = 404,492.94/721.30
  6. Step 6: Final answer
    x = 560.78

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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.