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Finding the Fourth Proportional to 213.39, 320.39 and 136.68

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Solution

The fourth proportional to 213.39, 320.39 and 136.68 is: 205.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    213.39 : 320.39 = 136.68 : x
  2. Step 2: Convert to fraction form
    213.39/320.39 = 136.68/x
  3. Step 3: Cross multiply
    213.39x = 320.39 × 136.68
  4. Step 4: Simplify right side
    213.39x = 43,790.22
  5. Step 5: Solve for x
    x = 43,790.22/213.39
  6. Step 6: Final answer
    x = 205.21

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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.