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Finding the Fourth Proportional to 84.79, 127.22 and 30.72

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Solution

The fourth proportional to 84.79, 127.22 and 30.72 is: 46.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.79 : 127.22 = 30.72 : x
  2. Step 2: Convert to fraction form
    84.79/127.22 = 30.72/x
  3. Step 3: Cross multiply
    84.79x = 127.22 × 30.72
  4. Step 4: Simplify right side
    84.79x = 3,908.20
  5. Step 5: Solve for x
    x = 3,908.20/84.79
  6. Step 6: Final answer
    x = 46.09

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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.