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Finding the Fourth Proportional to 661.11, 912.11 and 408.77

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Solution

The fourth proportional to 661.11, 912.11 and 408.77 is: 563.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.11 : 912.11 = 408.77 : x
  2. Step 2: Convert to fraction form
    661.11/912.11 = 408.77/x
  3. Step 3: Cross multiply
    661.11x = 912.11 × 408.77
  4. Step 4: Simplify right side
    661.11x = 372,843.20
  5. Step 5: Solve for x
    x = 372,843.20/661.11
  6. Step 6: Final answer
    x = 563.97

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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.