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Finding the Fourth Proportional to 119.30, 179.09 and 78.80

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Solution

The fourth proportional to 119.30, 179.09 and 78.80 is: 118.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    119.30 : 179.09 = 78.80 : x
  2. Step 2: Convert to fraction form
    119.30/179.09 = 78.80/x
  3. Step 3: Cross multiply
    119.30x = 179.09 × 78.80
  4. Step 4: Simplify right side
    119.30x = 14,111.90
  5. Step 5: Solve for x
    x = 14,111.90/119.30
  6. Step 6: Final answer
    x = 118.29

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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.