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Finding the Fourth Proportional to 209.70, 289.34 and 126.79

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Solution

The fourth proportional to 209.70, 289.34 and 126.79 is: 174.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.70 : 289.34 = 126.79 : x
  2. Step 2: Convert to fraction form
    209.70/289.34 = 126.79/x
  3. Step 3: Cross multiply
    209.70x = 289.34 × 126.79
  4. Step 4: Simplify right side
    209.70x = 36,685.74
  5. Step 5: Solve for x
    x = 36,685.74/209.70
  6. Step 6: Final answer
    x = 174.94

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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.