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Finding the Fourth Proportional to 86.31, 119.07 and 85.23

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Solution

The fourth proportional to 86.31, 119.07 and 85.23 is: 117.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.31 : 119.07 = 85.23 : x
  2. Step 2: Convert to fraction form
    86.31/119.07 = 85.23/x
  3. Step 3: Cross multiply
    86.31x = 119.07 × 85.23
  4. Step 4: Simplify right side
    86.31x = 10,148.34
  5. Step 5: Solve for x
    x = 10,148.34/86.31
  6. Step 6: Final answer
    x = 117.58

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.