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Finding the Fourth Proportional to 120.79, 180.78 and 119.17

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Solution

The fourth proportional to 120.79, 180.78 and 119.17 is: 178.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.79 : 180.78 = 119.17 : x
  2. Step 2: Convert to fraction form
    120.79/180.78 = 119.17/x
  3. Step 3: Cross multiply
    120.79x = 180.78 × 119.17
  4. Step 4: Simplify right side
    120.79x = 21,542.65
  5. Step 5: Solve for x
    x = 21,542.65/120.79
  6. Step 6: Final answer
    x = 178.35

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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.