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Finding the Fourth Proportional to 720.20, 993.87 and 401.15

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Solution

The fourth proportional to 720.20, 993.87 and 401.15 is: 553.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.20 : 993.87 = 401.15 : x
  2. Step 2: Convert to fraction form
    720.20/993.87 = 401.15/x
  3. Step 3: Cross multiply
    720.20x = 993.87 × 401.15
  4. Step 4: Simplify right side
    720.20x = 398,690.95
  5. Step 5: Solve for x
    x = 398,690.95/720.20
  6. Step 6: Final answer
    x = 553.58

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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.