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Finding the Fourth Proportional to 137.71, 206.53 and 79.89

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Solution

The fourth proportional to 137.71, 206.53 and 79.89 is: 119.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.71 : 206.53 = 79.89 : x
  2. Step 2: Convert to fraction form
    137.71/206.53 = 79.89/x
  3. Step 3: Cross multiply
    137.71x = 206.53 × 79.89
  4. Step 4: Simplify right side
    137.71x = 16,498.65
  5. Step 5: Solve for x
    x = 16,498.65/137.71
  6. Step 6: Final answer
    x = 119.81

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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.