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Finding the Fourth Proportional to 721.20, 1,086.01 and 699.67

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Solution

The fourth proportional to 721.20, 1,086.01 and 699.67 is: 1,053.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.20 : 1,086.01 = 699.67 : x
  2. Step 2: Convert to fraction form
    721.20/1,086.01 = 699.67/x
  3. Step 3: Cross multiply
    721.20x = 1,086.01 × 699.67
  4. Step 4: Simplify right side
    721.20x = 759,848.62
  5. Step 5: Solve for x
    x = 759,848.62/721.20
  6. Step 6: Final answer
    x = 1,053.59

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.