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Finding the Fourth Proportional to 120.99, 181.17 and 72.75

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Solution

The fourth proportional to 120.99, 181.17 and 72.75 is: 108.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.99 : 181.17 = 72.75 : x
  2. Step 2: Convert to fraction form
    120.99/181.17 = 72.75/x
  3. Step 3: Cross multiply
    120.99x = 181.17 × 72.75
  4. Step 4: Simplify right side
    120.99x = 13,180.12
  5. Step 5: Solve for x
    x = 13,180.12/120.99
  6. Step 6: Final answer
    x = 108.94

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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.