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Finding the Fourth Proportional to 79.86, 119.67 and 38.70

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Solution

The fourth proportional to 79.86, 119.67 and 38.70 is: 57.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.86 : 119.67 = 38.70 : x
  2. Step 2: Convert to fraction form
    79.86/119.67 = 38.70/x
  3. Step 3: Cross multiply
    79.86x = 119.67 × 38.70
  4. Step 4: Simplify right side
    79.86x = 4,631.23
  5. Step 5: Solve for x
    x = 4,631.23/79.86
  6. Step 6: Final answer
    x = 57.99

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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.