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Finding the Fourth Proportional to 79.89, 110.25 and 66.12

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Solution

The fourth proportional to 79.89, 110.25 and 66.12 is: 91.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.89 : 110.25 = 66.12 : x
  2. Step 2: Convert to fraction form
    79.89/110.25 = 66.12/x
  3. Step 3: Cross multiply
    79.89x = 110.25 × 66.12
  4. Step 4: Simplify right side
    79.89x = 7,289.73
  5. Step 5: Solve for x
    x = 7,289.73/79.89
  6. Step 6: Final answer
    x = 91.25

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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.