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Finding the Fourth Proportional to 209.70, 289.28 and 135.89

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Solution

The fourth proportional to 209.70, 289.28 and 135.89 is: 187.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.70 : 289.28 = 135.89 : x
  2. Step 2: Convert to fraction form
    209.70/289.28 = 135.89/x
  3. Step 3: Cross multiply
    209.70x = 289.28 × 135.89
  4. Step 4: Simplify right side
    209.70x = 39,310.30
  5. Step 5: Solve for x
    x = 39,310.30/209.70
  6. Step 6: Final answer
    x = 187.46

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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.