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Finding the Fourth Proportional to 79.71, 119.29 and 72.86

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Solution

The fourth proportional to 79.71, 119.29 and 72.86 is: 109.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.71 : 119.29 = 72.86 : x
  2. Step 2: Convert to fraction form
    79.71/119.29 = 72.86/x
  3. Step 3: Cross multiply
    79.71x = 119.29 × 72.86
  4. Step 4: Simplify right side
    79.71x = 8,691.47
  5. Step 5: Solve for x
    x = 8,691.47/79.71
  6. Step 6: Final answer
    x = 109.04

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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.