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Finding the Fourth Proportional to 661.28, 991.92 and 271.49

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Solution

The fourth proportional to 661.28, 991.92 and 271.49 is: 407.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.28 : 991.92 = 271.49 : x
  2. Step 2: Convert to fraction form
    661.28/991.92 = 271.49/x
  3. Step 3: Cross multiply
    661.28x = 991.92 × 271.49
  4. Step 4: Simplify right side
    661.28x = 269,295.68
  5. Step 5: Solve for x
    x = 269,295.68/661.28
  6. Step 6: Final answer
    x = 407.24

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.