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Finding the Fourth Proportional to 720.62, 994.50 and 405.90

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Solution

The fourth proportional to 720.62, 994.50 and 405.90 is: 560.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.62 : 994.50 = 405.90 : x
  2. Step 2: Convert to fraction form
    720.62/994.50 = 405.90/x
  3. Step 3: Cross multiply
    720.62x = 994.50 × 405.90
  4. Step 4: Simplify right side
    720.62x = 403,667.55
  5. Step 5: Solve for x
    x = 403,667.55/720.62
  6. Step 6: Final answer
    x = 560.17

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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.