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Finding the Fourth Proportional to 661.43, 911.96 and 439.90

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Solution

The fourth proportional to 661.43, 911.96 and 439.90 is: 606.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.43 : 911.96 = 439.90 : x
  2. Step 2: Convert to fraction form
    661.43/911.96 = 439.90/x
  3. Step 3: Cross multiply
    661.43x = 911.96 × 439.90
  4. Step 4: Simplify right side
    661.43x = 401,168.37
  5. Step 5: Solve for x
    x = 401,168.37/661.43
  6. Step 6: Final answer
    x = 606.51

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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.