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Finding the Fourth Proportional to 86.15, 127.60 and 85.25

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Solution

The fourth proportional to 86.15, 127.60 and 85.25 is: 126.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.15 : 127.60 = 85.25 : x
  2. Step 2: Convert to fraction form
    86.15/127.60 = 85.25/x
  3. Step 3: Cross multiply
    86.15x = 127.60 × 85.25
  4. Step 4: Simplify right side
    86.15x = 10,878.01
  5. Step 5: Solve for x
    x = 10,878.01/86.15
  6. Step 6: Final answer
    x = 126.26

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.