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Finding the Fourth Proportional to 721.32, 989.04 and 651.12

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Solution

The fourth proportional to 721.32, 989.04 and 651.12 is: 892.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.32 : 989.04 = 651.12 : x
  2. Step 2: Convert to fraction form
    721.32/989.04 = 651.12/x
  3. Step 3: Cross multiply
    721.32x = 989.04 × 651.12
  4. Step 4: Simplify right side
    721.32x = 643,983.72
  5. Step 5: Solve for x
    x = 643,983.72/721.32
  6. Step 6: Final answer
    x = 892.79

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.