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Finding the Fourth Proportional to 205.67, 308.40 and 66.81

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Solution

The fourth proportional to 205.67, 308.40 and 66.81 is: 100.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.67 : 308.40 = 66.81 : x
  2. Step 2: Convert to fraction form
    205.67/308.40 = 66.81/x
  3. Step 3: Cross multiply
    205.67x = 308.40 × 66.81
  4. Step 4: Simplify right side
    205.67x = 20,604.20
  5. Step 5: Solve for x
    x = 20,604.20/205.67
  6. Step 6: Final answer
    x = 100.18

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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.