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Finding the Fourth Proportional to 120.85, 181.24 and 80.28

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Solution

The fourth proportional to 120.85, 181.24 and 80.28 is: 120.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.85 : 181.24 = 80.28 : x
  2. Step 2: Convert to fraction form
    120.85/181.24 = 80.28/x
  3. Step 3: Cross multiply
    120.85x = 181.24 × 80.28
  4. Step 4: Simplify right side
    120.85x = 14,549.75
  5. Step 5: Solve for x
    x = 14,549.75/120.85
  6. Step 6: Final answer
    x = 120.40

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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.