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Finding the Fourth Proportional to 86.70, 119.67 and 83.70

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Solution

The fourth proportional to 86.70, 119.67 and 83.70 is: 115.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.70 : 119.67 = 83.70 : x
  2. Step 2: Convert to fraction form
    86.70/119.67 = 83.70/x
  3. Step 3: Cross multiply
    86.70x = 119.67 × 83.70
  4. Step 4: Simplify right side
    86.70x = 10,016.38
  5. Step 5: Solve for x
    x = 10,016.38/86.70
  6. Step 6: Final answer
    x = 115.53

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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.