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Finding the Fourth Proportional to 85.02, 128.27 and 80.52

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Solution

The fourth proportional to 85.02, 128.27 and 80.52 is: 121.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.02 : 128.27 = 80.52 : x
  2. Step 2: Convert to fraction form
    85.02/128.27 = 80.52/x
  3. Step 3: Cross multiply
    85.02x = 128.27 × 80.52
  4. Step 4: Simplify right side
    85.02x = 10,327.90
  5. Step 5: Solve for x
    x = 10,327.90/85.02
  6. Step 6: Final answer
    x = 121.48

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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.