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Finding the Fourth Proportional to 721.13, 995.16 and 389.56

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Solution

The fourth proportional to 721.13, 995.16 and 389.56 is: 537.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.13 : 995.16 = 389.56 : x
  2. Step 2: Convert to fraction form
    721.13/995.16 = 389.56/x
  3. Step 3: Cross multiply
    721.13x = 995.16 × 389.56
  4. Step 4: Simplify right side
    721.13x = 387,674.25
  5. Step 5: Solve for x
    x = 387,674.25/721.13
  6. Step 6: Final answer
    x = 537.59

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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.