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Finding the Fourth Proportional to 137.65, 205.99 and 79.71

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Solution

The fourth proportional to 137.65, 205.99 and 79.71 is: 119.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.65 : 205.99 = 79.71 : x
  2. Step 2: Convert to fraction form
    137.65/205.99 = 79.71/x
  3. Step 3: Cross multiply
    137.65x = 205.99 × 79.71
  4. Step 4: Simplify right side
    137.65x = 16,419.46
  5. Step 5: Solve for x
    x = 16,419.46/137.65
  6. Step 6: Final answer
    x = 119.28

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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.