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Finding the Fourth Proportional to 720.36, 994.07 and 405.70

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Solution

The fourth proportional to 720.36, 994.07 and 405.70 is: 559.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.36 : 994.07 = 405.70 : x
  2. Step 2: Convert to fraction form
    720.36/994.07 = 405.70/x
  3. Step 3: Cross multiply
    720.36x = 994.07 × 405.70
  4. Step 4: Simplify right side
    720.36x = 403,294.20
  5. Step 5: Solve for x
    x = 403,294.20/720.36
  6. Step 6: Final answer
    x = 559.85

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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.