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Finding the Fourth Proportional to 85.85, 118.22 and 65.09

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Solution

The fourth proportional to 85.85, 118.22 and 65.09 is: 89.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.85 : 118.22 = 65.09 : x
  2. Step 2: Convert to fraction form
    85.85/118.22 = 65.09/x
  3. Step 3: Cross multiply
    85.85x = 118.22 × 65.09
  4. Step 4: Simplify right side
    85.85x = 7,694.02
  5. Step 5: Solve for x
    x = 7,694.02/85.85
  6. Step 6: Final answer
    x = 89.63

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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.