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Finding the Fourth Proportional to 661.18, 991.77 and 271.39

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Solution

The fourth proportional to 661.18, 991.77 and 271.39 is: 407.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.18 : 991.77 = 271.39 : x
  2. Step 2: Convert to fraction form
    661.18/991.77 = 271.39/x
  3. Step 3: Cross multiply
    661.18x = 991.77 × 271.39
  4. Step 4: Simplify right side
    661.18x = 269,156.46
  5. Step 5: Solve for x
    x = 269,156.46/661.18
  6. Step 6: Final answer
    x = 407.09

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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.