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Finding the Fourth Proportional to 85.03, 117.30 and 66.61

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Solution

The fourth proportional to 85.03, 117.30 and 66.61 is: 91.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.03 : 117.30 = 66.61 : x
  2. Step 2: Convert to fraction form
    85.03/117.30 = 66.61/x
  3. Step 3: Cross multiply
    85.03x = 117.30 × 66.61
  4. Step 4: Simplify right side
    85.03x = 7,813.35
  5. Step 5: Solve for x
    x = 7,813.35/85.03
  6. Step 6: Final answer
    x = 91.89

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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.