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Finding the Fourth Proportional to 120.80, 165.96 and 98.92

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Solution

The fourth proportional to 120.80, 165.96 and 98.92 is: 135.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.80 : 165.96 = 98.92 : x
  2. Step 2: Convert to fraction form
    120.80/165.96 = 98.92/x
  3. Step 3: Cross multiply
    120.80x = 165.96 × 98.92
  4. Step 4: Simplify right side
    120.80x = 16,416.76
  5. Step 5: Solve for x
    x = 16,416.76/120.80
  6. Step 6: Final answer
    x = 135.90

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.