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Finding the Fourth Proportional to 120.26, 180.09 and 99.87

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Solution

The fourth proportional to 120.26, 180.09 and 99.87 is: 149.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.26 : 180.09 = 99.87 : x
  2. Step 2: Convert to fraction form
    120.26/180.09 = 99.87/x
  3. Step 3: Cross multiply
    120.26x = 180.09 × 99.87
  4. Step 4: Simplify right side
    120.26x = 17,985.59
  5. Step 5: Solve for x
    x = 17,985.59/120.26
  6. Step 6: Final answer
    x = 149.56

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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.