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Finding the Fourth Proportional to 72.05, 108.14 and 66.15

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Solution

The fourth proportional to 72.05, 108.14 and 66.15 is: 99.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.05 : 108.14 = 66.15 : x
  2. Step 2: Convert to fraction form
    72.05/108.14 = 66.15/x
  3. Step 3: Cross multiply
    72.05x = 108.14 × 66.15
  4. Step 4: Simplify right side
    72.05x = 7,153.13
  5. Step 5: Solve for x
    x = 7,153.13/72.05
  6. Step 6: Final answer
    x = 99.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.