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Finding the Fourth Proportional to 84.89, 127.49 and 72.20

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Solution

The fourth proportional to 84.89, 127.49 and 72.20 is: 108.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.89 : 127.49 = 72.20 : x
  2. Step 2: Convert to fraction form
    84.89/127.49 = 72.20/x
  3. Step 3: Cross multiply
    84.89x = 127.49 × 72.20
  4. Step 4: Simplify right side
    84.89x = 9,204.74
  5. Step 5: Solve for x
    x = 9,204.74/84.89
  6. Step 6: Final answer
    x = 108.43

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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.