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Finding the Fourth Proportional to 120.38, 180.28 and 66.12

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Solution

The fourth proportional to 120.38, 180.28 and 66.12 is: 99.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.38 : 180.28 = 66.12 : x
  2. Step 2: Convert to fraction form
    120.38/180.28 = 66.12/x
  3. Step 3: Cross multiply
    120.38x = 180.28 × 66.12
  4. Step 4: Simplify right side
    120.38x = 11,920.11
  5. Step 5: Solve for x
    x = 11,920.11/120.38
  6. Step 6: Final answer
    x = 99.02

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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.