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Finding the Fourth Proportional to 719.40, 992.72 and 408.90

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Solution

The fourth proportional to 719.40, 992.72 and 408.90 is: 564.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.40 : 992.72 = 408.90 : x
  2. Step 2: Convert to fraction form
    719.40/992.72 = 408.90/x
  3. Step 3: Cross multiply
    719.40x = 992.72 × 408.90
  4. Step 4: Simplify right side
    719.40x = 405,923.21
  5. Step 5: Solve for x
    x = 405,923.21/719.40
  6. Step 6: Final answer
    x = 564.25

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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.