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Finding the Fourth Proportional to 85.56, 129.03 and 84.36

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Solution

The fourth proportional to 85.56, 129.03 and 84.36 is: 127.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.56 : 129.03 = 84.36 : x
  2. Step 2: Convert to fraction form
    85.56/129.03 = 84.36/x
  3. Step 3: Cross multiply
    85.56x = 129.03 × 84.36
  4. Step 4: Simplify right side
    85.56x = 10,884.97
  5. Step 5: Solve for x
    x = 10,884.97/85.56
  6. Step 6: Final answer
    x = 127.22

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.