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Finding the Fourth Proportional to 84.70, 127.05 and 54.19

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Solution

The fourth proportional to 84.70, 127.05 and 54.19 is: 81.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.70 : 127.05 = 54.19 : x
  2. Step 2: Convert to fraction form
    84.70/127.05 = 54.19/x
  3. Step 3: Cross multiply
    84.70x = 127.05 × 54.19
  4. Step 4: Simplify right side
    84.70x = 6,884.84
  5. Step 5: Solve for x
    x = 6,884.84/84.70
  6. Step 6: Final answer
    x = 81.29

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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.