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Finding the Fourth Proportional to 120.86, 180.84 and 105.84

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Solution

The fourth proportional to 120.86, 180.84 and 105.84 is: 158.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.86 : 180.84 = 105.84 : x
  2. Step 2: Convert to fraction form
    120.86/180.84 = 105.84/x
  3. Step 3: Cross multiply
    120.86x = 180.84 × 105.84
  4. Step 4: Simplify right side
    120.86x = 19,140.11
  5. Step 5: Solve for x
    x = 19,140.11/120.86
  6. Step 6: Final answer
    x = 158.37

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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.