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Finding the Fourth Proportional to 85.09, 127.63 and 20.96

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Solution

The fourth proportional to 85.09, 127.63 and 20.96 is: 31.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.09 : 127.63 = 20.96 : x
  2. Step 2: Convert to fraction form
    85.09/127.63 = 20.96/x
  3. Step 3: Cross multiply
    85.09x = 127.63 × 20.96
  4. Step 4: Simplify right side
    85.09x = 2,675.12
  5. Step 5: Solve for x
    x = 2,675.12/85.09
  6. Step 6: Final answer
    x = 31.44

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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.