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Finding the Fourth Proportional to 86.80, 119.79 and 49.97

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Solution

The fourth proportional to 86.80, 119.79 and 49.97 is: 68.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.80 : 119.79 = 49.97 : x
  2. Step 2: Convert to fraction form
    86.80/119.79 = 49.97/x
  3. Step 3: Cross multiply
    86.80x = 119.79 × 49.97
  4. Step 4: Simplify right side
    86.80x = 5,985.91
  5. Step 5: Solve for x
    x = 5,985.91/86.80
  6. Step 6: Final answer
    x = 68.96

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.