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Finding the Fourth Proportional to 205.79, 284.06 and 121.85

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Solution

The fourth proportional to 205.79, 284.06 and 121.85 is: 168.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.79 : 284.06 = 121.85 : x
  2. Step 2: Convert to fraction form
    205.79/284.06 = 121.85/x
  3. Step 3: Cross multiply
    205.79x = 284.06 × 121.85
  4. Step 4: Simplify right side
    205.79x = 34,612.71
  5. Step 5: Solve for x
    x = 34,612.71/205.79
  6. Step 6: Final answer
    x = 168.19

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.